diff --git a/proto/tendermint/blocksync/types.proto b/proto/tendermint/blocksync/types.proto
index 4febfd145..67da76dce 100644
--- a/proto/tendermint/blocksync/types.proto
+++ b/proto/tendermint/blocksync/types.proto
@@ -4,6 +4,7 @@ package tendermint.blocksync;
 option go_package = "github.com/tendermint/tendermint/proto/tendermint/blocksync";
 
 import "tendermint/types/block.proto";
+import "tendermint/types/types.proto";
 
 // BlockRequest requests a block for a specific height
 message BlockRequest {
@@ -19,6 +20,7 @@ message NoBlockResponse {
 // BlockResponse returns block to the requested
 message BlockResponse {
   tendermint.types.Block block = 1;
+  tendermint.types.ExtendedCommit ext_commit = 2;
 }
 
 // StatusRequest requests the status of a peer.
diff --git a/proto/tendermint/types/types.proto b/proto/tendermint/types/types.proto
index e2b8a46c8..7e7e6f3af 100644
--- a/proto/tendermint/types/types.proto
+++ b/proto/tendermint/types/types.proto
@@ -142,6 +142,24 @@ message CommitSig {
   bytes signature = 4;
 }
 
+message ExtendedCommit {
+  int64   height   = 1;
+  int32   round    = 2;
+  BlockID block_id = 3
+      [(gogoproto.nullable) = false, (gogoproto.customname) = "BlockID"];
+  repeated ExtendedCommitSig extended_signatures = 4 [(gogoproto.nullable) = false];
+}
+
+message ExtendedCommitSig {
+  BlockIDFlag               block_id_flag     = 1;
+  bytes                     validator_address = 2;
+  google.protobuf.Timestamp timestamp         = 3
+      [(gogoproto.nullable) = false, (gogoproto.stdtime) = true];
+  bytes signature = 4;
+  bytes vote_extension = 5;
+  bytes extension_signature = 6;
+}
+
 message Proposal {
   SignedMsgType type      = 1;
   int64         height    = 2;