diff --git a/istclient/client.go b/istclient/client.go
index 372cece2..b75ecf49 100644
--- a/istclient/client.go
+++ b/istclient/client.go
@@ -66,6 +66,17 @@ func (ic *Client) AdminPeers(ctx context.Context) ([]*p2p.PeerInfo, error) {
 	return r, err
 }
 
+// ----------------------------------------------------------------------------
+func (ic *Client) BlockNumber(ctx context.Context) (*big.Int, error) {
+	var r string
+	err := ic.c.CallContext(ctx, &r, "eth_blockNumber")
+	if err != nil {
+		return nil, err
+	}
+	h, err := hexutil.DecodeBig(r)
+	return h, err
+}
+
 // ----------------------------------------------------------------------------
 
 func (ic *Client) StartMining(ctx context.Context) error {
diff --git a/tests/integration_test.go b/tests/integration_test.go
index 4e2f6b43..cd531850 100644
--- a/tests/integration_test.go
+++ b/tests/integration_test.go
@@ -35,7 +35,7 @@ var _ = Describe("4 validators Istanbul", func() {
 		blockchain container.Blockchain
 	)
 
-	BeforeSuite(func() {
+	BeforeEach(func() {
 		blockchain = container.NewBlockchain(
 			numberOfValidators,
 			container.ImageRepository("quay.io/amis/geth"),
@@ -55,7 +55,7 @@ var _ = Describe("4 validators Istanbul", func() {
 		Expect(blockchain.Start()).To(BeNil())
 	})
 
-	AfterSuite(func() {
+	AfterEach(func() {
 		Expect(blockchain.Stop()).To(BeNil())
 		blockchain.Finalize()
 	})
diff --git a/tests/non_byzantine_faulty_test.go b/tests/non_byzantine_faulty_test.go
new file mode 100644
index 00000000..9c5e1ff6
--- /dev/null
+++ b/tests/non_byzantine_faulty_test.go
@@ -0,0 +1,108 @@
+// Copyright 2017 AMIS Technologies
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package tests
+
+import (
+	"context"
+	"time"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"github.com/getamis/istanbul-tools/container"
+)
+
+var _ = Describe("TSU-04: Non-Byzantine Faulty", func() {
+	const (
+		numberOfValidators = 4
+	)
+	var (
+		blockchain container.Blockchain
+	)
+
+	BeforeEach(func() {
+		blockchain = container.NewBlockchain(
+			numberOfValidators,
+			container.ImageRepository("quay.io/amis/geth"),
+			container.ImageTag("istanbul_develop"),
+			container.DataDir("/data"),
+			container.WebSocket(),
+			container.WebSocketAddress("0.0.0.0"),
+			container.WebSocketAPI("admin,eth,net,web3,personal,miner"),
+			container.WebSocketOrigin("*"),
+			container.NAT("any"),
+			container.NoDiscover(),
+			container.Etherbase("1a9afb711302c5f83b5902843d1c007a1a137632"),
+			container.Mine(),
+			container.Logging(false),
+		)
+
+		Expect(blockchain.Start()).To(BeNil())
+	})
+
+	AfterEach(func() {
+		blockchain.Stop() // This will return container not found error since we stop one
+		blockchain.Finalize()
+	})
+
+	It("TSU-04-01: Stop F validators", func(done Done) {
+
+		By("Generating blocks")
+		v0 := blockchain.Validators()[0]
+		c0 := v0.NewIstanbulClient()
+		ticker := time.NewTicker(time.Millisecond * 100)
+		for _ = range ticker.C {
+			n, e := c0.BlockNumber(context.Background())
+			Expect(e).To(BeNil())
+			// Check if new blocks are getting generated
+			if n.Int64() > 1 {
+				ticker.Stop()
+				break
+			}
+		}
+		By("Stopping validator 0")
+		e := v0.Stop()
+		Expect(e).To(BeNil())
+
+		ticker = time.NewTicker(time.Millisecond * 100)
+		for _ = range ticker.C {
+			e := v0.Stop()
+			// Wait for e to be non-nil to make sure the container is down
+			if e != nil {
+				ticker.Stop()
+				break
+			}
+		}
+
+		By("Checking blockchain progress")
+		v1 := blockchain.Validators()[1]
+		c1 := v1.NewIstanbulClient()
+		n1, e := c1.BlockNumber(context.Background())
+		Expect(e).To(BeNil())
+		ticker = time.NewTicker(time.Millisecond * 100)
+		for _ = range ticker.C {
+			newN1, e := c1.BlockNumber(context.Background())
+			Expect(e).To(BeNil())
+			if newN1.Int64() > n1.Int64() {
+				ticker.Stop()
+				break
+			}
+		}
+
+		close(done)
+	}, 60)
+})