diff --git a/conn.go b/conn.go
index 5e998fd..c11aebf 100644
--- a/conn.go
+++ b/conn.go
@@ -50,17 +50,19 @@ func (up *upTrack) notifyLocal(add bool, track downTrack) {
 	}
 }
 
-func (up *upTrack) addLocal(local downTrack) {
+func (up *upTrack) addLocal(local downTrack) error {
 	up.mu.Lock()
 	for _, t := range up.local {
 		if t == local {
 			up.mu.Unlock()
-			return
+			return nil
 		}
 	}
 	up.local = append(up.local, local)
 	up.mu.Unlock()
+
 	up.notifyLocal(true, local)
+	return nil
 }
 
 func (up *upTrack) delLocal(local downTrack) bool {
@@ -107,20 +109,26 @@ type upConnection struct {
 	labels        map[string]string
 	iceCandidates []*webrtc.ICECandidateInit
 
-	mu    sync.Mutex
-	local []downConnection
+	mu     sync.Mutex
+	closed bool
+	local  []downConnection
 }
 
-func (up *upConnection) addLocal(local downConnection) {
+var ErrConnectionClosed = errors.New("connection is closed")
+
+func (up *upConnection) addLocal(local downConnection) error {
 	up.mu.Lock()
 	defer up.mu.Unlock()
+	if up.closed {
+		return ErrConnectionClosed
+	}
 	for _, t := range up.local {
 		if t == local {
-			up.mu.Unlock()
-			return
+			return nil
 		}
 	}
 	up.local = append(up.local, local)
+	return nil
 }
 
 func (up *upConnection) delLocal(local downConnection) bool {
@@ -143,6 +151,21 @@ func (up *upConnection) getLocal() []downConnection {
 	return local
 }
 
+func (up *upConnection) Close() error {
+	up.mu.Lock()
+	defer up.mu.Unlock()
+
+	go func(local []downConnection) {
+		for _, l := range local {
+			l.Close()
+		}
+	}(up.local)
+
+	up.local = nil
+	up.closed = true
+	return up.pc.Close()
+}
+
 func (up *upConnection) addICECandidate(candidate *webrtc.ICECandidateInit) error {
 	if up.pc.RemoteDescription() != nil {
 		return up.pc.AddICECandidate(*candidate)
diff --git a/disk.go b/disk.go
index 8b85090..097dd72 100644
--- a/disk.go
+++ b/disk.go
@@ -194,7 +194,10 @@ func newDiskConn(directory, label string, up *upConnection, remoteTracks []*upTr
 		}
 	}
 
-	up.addLocal(&conn)
+	err := up.addLocal(&conn)
+	if err != nil {
+		return nil, err
+	}
 
 	return &conn, nil
 }
diff --git a/webclient.go b/webclient.go
index dca06a6..346fe54 100644
--- a/webclient.go
+++ b/webclient.go
@@ -675,14 +675,7 @@ func delUpConn(c *webClient, id string) bool {
 		}
 	}
 
-	local := conn.getLocal()
-	go func() {
-		for _, l := range local {
-			l.Close()
-		}
-	}()
-
-	conn.pc.Close()
+	conn.Close()
 	delete(c.up, id)
 	return true
 }
@@ -744,9 +737,13 @@ func addDownConn(c *webClient, id string, remote *upConnection) (*rtpDownConnect
 		conn.pc.Close()
 		return nil, errors.New("Adding duplicate connection")
 	}
-	c.down[id] = conn
+	err = remote.addLocal(conn)
+	if err != nil {
+		conn.pc.Close()
+		return nil, err
+	}
 
-	remote.addLocal(conn)
+	c.down[id] = conn
 	return conn, nil
 }