diff --git a/eth/backend.go b/eth/backend.go
index 5f7fc7066b..8b17d927ec 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -189,8 +189,8 @@ func New(ctx *node.ServiceContext, config *Config) (*Ethereum, error) {
 	if eth.chainConfig.Posv != nil {
 		c := eth.engine.(*posv.Posv)
 
-		// Hook sends tx sign to smartcontract after inserting block to chain.
-		importedHook := func(block *types.Block) error {
+		// Hook double validation
+		doubleValidateHook := func(block *types.Block) error {
 			snap, err := c.GetSnapshot(eth.blockchain, block.Header())
 			if err != nil {
 				if err == consensus.ErrUnknownAncestor {
@@ -199,7 +199,6 @@ func New(ctx *node.ServiceContext, config *Config) (*Ethereum, error) {
 				return fmt.Errorf("Fail to get snapshot for sign tx validator: %v", err)
 			}
 			if _, authorized := snap.Signers[eth.etherbase]; authorized {
-				// double validation
 				m2, err := getM2(snap, eth, block)
 				if err != nil {
 					return fmt.Errorf("Fail to validate M2 condition for importing block: %v", err)
@@ -216,9 +215,6 @@ func New(ctx *node.ServiceContext, config *Config) (*Ethereum, error) {
 					if len(txsSentFromM2) > 0 {
 						for _, tx := range txsSentFromM2 {
 							if tx.To().String() == common.BlockSigners {
-								if err := contracts.CreateTransactionSign(chainConfig, eth.txPool, eth.accountManager, block, chainDb); err != nil {
-									return fmt.Errorf("Fail to create tx sign for importing block: %v", err)
-								}
 								return nil
 							}
 						}
@@ -226,29 +222,32 @@ func New(ctx *node.ServiceContext, config *Config) (*Ethereum, error) {
 					//then wait until signTx from m2 comes into txPool
 					txCh := make(chan core.TxPreEvent, txChanSize)
 					subEvent := eth.txPool.SubscribeTxPreEvent(txCh)
-				G:
 					select {
 					case event := <-txCh:
 						from, err := eth.txPool.GetSender(event.Tx)
 						if (err == nil) && (event.Tx.To().String() == common.BlockSigners) && (from == m2) {
-							if err := contracts.CreateTransactionSign(chainConfig, eth.txPool, eth.accountManager, block, chainDb); err != nil {
-								return fmt.Errorf("Fail to create tx sign for importing block: %v", err)
-							}
 							return nil
 						}
 					//timeout 10s
 					case <-time.After(time.Duration(10) * time.Second):
-						break G
+						return fmt.Errorf("Time out waiting for confirmation from m2")
 					}
 					subEvent.Unsubscribe()
-				} else if err := contracts.CreateTransactionSign(chainConfig, eth.txPool, eth.accountManager, block, chainDb); err != nil {
-					return fmt.Errorf("Fail to create tx sign for importing block: %v", err)
 				}
-				// end of double validation
+				return nil
+			}
+			return fmt.Errorf("This address is not authorized to validate block")
+		}
+
+		signHook := func(block *types.Block) error {
+			if err := contracts.CreateTransactionSign(chainConfig, eth.txPool, eth.accountManager, block, chainDb); err != nil {
+				return fmt.Errorf("Fail to create tx sign for importing block: %v", err)
 			}
 			return nil
 		}
-		eth.protocolManager.fetcher.SetImportedHook(importedHook)
+
+		eth.protocolManager.fetcher.SetDoubleValidateHook(doubleValidateHook)
+		eth.protocolManager.fetcher.SetSignHook(signHook)
 
 		// Hook prepares validators M2 for the current epoch
 		c.HookValidator = func(header *types.Header, signers []common.Address) error {
diff --git a/eth/fetcher/fetcher.go b/eth/fetcher/fetcher.go
index 94ac16e405..e75ecdbfa5 100644
--- a/eth/fetcher/fetcher.go
+++ b/eth/fetcher/fetcher.go
@@ -138,11 +138,12 @@ type Fetcher struct {
 	dropPeer       peerDropFn         // Drops a peer for misbehaving
 
 	// Testing hooks
-	announceChangeHook func(common.Hash, bool)  // Method to call upon adding or deleting a hash from the announce list
-	queueChangeHook    func(common.Hash, bool)  // Method to call upon adding or deleting a block from the import queue
-	fetchingHook       func([]common.Hash)      // Method to call upon starting a block (eth/61) or header (eth/62) fetch
-	completingHook     func([]common.Hash)      // Method to call upon starting a block body fetch (eth/62)
-	importedHook       func(*types.Block) error // Method to call upon successful block import (both eth/61 and eth/62)
+	announceChangeHook func(common.Hash, bool) // Method to call upon adding or deleting a hash from the announce list
+	queueChangeHook    func(common.Hash, bool) // Method to call upon adding or deleting a block from the import queue
+	fetchingHook       func([]common.Hash)     // Method to call upon starting a block (eth/61) or header (eth/62) fetch
+	completingHook     func([]common.Hash)     // Method to call upon starting a block body fetch (eth/62)
+	doubleValidateHook func(*types.Block) error
+	signHook           func(*types.Block) error
 }
 
 // New creates a block fetcher to retrieve blocks based on hash announcements.
@@ -665,9 +666,9 @@ func (f *Fetcher) insert(peer string, block *types.Block) {
 			f.dropPeer(peer)
 			return
 		}
-		// Invoke the imported hook to run double validation layer
-		if f.importedHook != nil {
-			if err := f.importedHook(block); err != nil {
+		// Invoke the dv hook to run double validation layer
+		if f.doubleValidateHook != nil {
+			if err := f.doubleValidateHook(block); err != nil {
 				log.Error("Double validation failed", "err", err, "Discard this block!")
 				return
 			}
@@ -678,6 +679,14 @@ func (f *Fetcher) insert(peer string, block *types.Block) {
 			log.Debug("Propagated block import failed", "peer", peer, "number", block.Number(), "hash", hash, "err", err)
 			return
 		}
+
+		if f.signHook != nil {
+			if err := f.signHook(block); err != nil {
+				log.Error("Can't sign the imported block", "err", err)
+				return
+			}
+		}
+
 		// If import succeeded, broadcast the block
 		propAnnounceOutTimer.UpdateSince(block.ReceivedAt)
 		go f.broadcastBlock(block, false)
@@ -739,7 +748,12 @@ func (f *Fetcher) forgetBlock(hash common.Hash) {
 	}
 }
 
-// Bind import hook when block imported into chain.
-func (f *Fetcher) SetImportedHook(importedHook func(*types.Block) error) {
-	f.importedHook = importedHook
+// Bind double validate hook before block imported into chain.
+func (f *Fetcher) SetDoubleValidateHook(doubleValidateHook func(*types.Block) error) {
+	f.doubleValidateHook = doubleValidateHook
+}
+
+// Bind double validate hook before block imported into chain.
+func (f *Fetcher) SetSignHook(signHook func(*types.Block) error) {
+	f.signHook = signHook
 }
diff --git a/eth/fetcher/fetcher_test.go b/eth/fetcher/fetcher_test.go
index fc16a0f5f3..af9a5a6b44 100644
--- a/eth/fetcher/fetcher_test.go
+++ b/eth/fetcher/fetcher_test.go
@@ -288,7 +288,7 @@ func testSequentialAnnouncements(t *testing.T, protocol int) {
 
 	// Iteratively announce blocks until all are imported
 	imported := make(chan *types.Block)
-	tester.fetcher.importedHook = func(block *types.Block) error {
+	tester.fetcher.signHook = func(block *types.Block) error {
 		imported <- block
 		return nil
 	}
@@ -329,7 +329,7 @@ func testConcurrentAnnouncements(t *testing.T, protocol int) {
 	}
 	// Iteratively announce blocks until all are imported
 	imported := make(chan *types.Block)
-	tester.fetcher.importedHook = func(block *types.Block) error {
+	tester.fetcher.signHook = func(block *types.Block) error {
 		imported <- block
 		return nil
 	}
@@ -369,7 +369,7 @@ func testOverlappingAnnouncements(t *testing.T, protocol int) {
 	for i := 0; i < overlap; i++ {
 		imported <- nil
 	}
-	tester.fetcher.importedHook = func(block *types.Block) error {
+	tester.fetcher.signHook = func(block *types.Block) error {
 		imported <- block
 		return nil
 	}
@@ -446,7 +446,7 @@ func testRandomArrivalImport(t *testing.T, protocol int) {
 
 	// Iteratively announce blocks, skipping one entry
 	imported := make(chan *types.Block, len(hashes)-1)
-	tester.fetcher.importedHook = func(block *types.Block) error {
+	tester.fetcher.signHook = func(block *types.Block) error {
 		imported <- block
 		return nil
 	}
@@ -480,7 +480,7 @@ func testQueueGapFill(t *testing.T, protocol int) {
 
 	// Iteratively announce blocks, skipping one entry
 	imported := make(chan *types.Block, len(hashes)-1)
-	tester.fetcher.importedHook = func(block *types.Block) error {
+	tester.fetcher.signHook = func(block *types.Block) error {
 		imported <- block
 		return nil
 	}
@@ -520,7 +520,7 @@ func testImportDeduplication(t *testing.T, protocol int) {
 	fetching := make(chan []common.Hash)
 	imported := make(chan *types.Block, len(hashes)-1)
 	tester.fetcher.fetchingHook = func(hashes []common.Hash) { fetching <- hashes }
-	tester.fetcher.importedHook = func(block *types.Block) error {
+	tester.fetcher.signHook = func(block *types.Block) error {
 		imported <- block
 		return nil
 	}
@@ -632,7 +632,7 @@ func testInvalidNumberAnnouncement(t *testing.T, protocol int) {
 	badBodyFetcher := tester.makeBodyFetcher("bad", blocks, 0)
 
 	imported := make(chan *types.Block)
-	tester.fetcher.importedHook = func(block *types.Block) error {
+	tester.fetcher.signHook = func(block *types.Block) error {
 		imported <- block
 		return nil
 	}
@@ -687,7 +687,7 @@ func testEmptyBlockShortCircuit(t *testing.T, protocol int) {
 	tester.fetcher.completingHook = func(hashes []common.Hash) { completing <- hashes }
 
 	imported := make(chan *types.Block)
-	tester.fetcher.importedHook = func(block *types.Block) error {
+	tester.fetcher.signHook = func(block *types.Block) error {
 		imported <- block
 		return nil
 	}
@@ -720,7 +720,7 @@ func testHashMemoryExhaustionAttack(t *testing.T, protocol int) {
 	tester := newTester()
 
 	imported, announces := make(chan *types.Block), int32(0)
-	tester.fetcher.importedHook = func(block *types.Block) error {
+	tester.fetcher.signHook = func(block *types.Block) error {
 		imported <- block
 		return nil
 	}
@@ -770,7 +770,7 @@ func TestBlockMemoryExhaustionAttack(t *testing.T) {
 	tester := newTester()
 
 	imported, enqueued := make(chan *types.Block), int32(0)
-	tester.fetcher.importedHook = func(block *types.Block) error {
+	tester.fetcher.signHook = func(block *types.Block) error {
 		imported <- block
 		return nil
 	}