diff --git a/lib/server/swarm.js b/lib/server/swarm.js
index f44f3cf..d07f061 100644
--- a/lib/server/swarm.js
+++ b/lib/server/swarm.js
@@ -21,15 +21,18 @@ Swarm.prototype.announce = function (params, cb) {
   // Mark the source peer as recently used in cache
   var peer = self.peers.get(id)
 
-  if (params.event === 'started') {
+  // Get the peer back in swarm if missing
+  if (params.event === 'started' || !peer) {
     self._onAnnounceStarted(params, peer)
-  } else if (params.event === 'stopped') {
+  }
+
+  if (params.event === 'stopped') {
     self._onAnnounceStopped(params, peer)
   } else if (params.event === 'completed') {
     self._onAnnounceCompleted(params, peer)
   } else if (params.event === 'update') {
     self._onAnnounceUpdate(params, peer)
-  } else {
+  } else if (params.event !== 'started') {
     cb(new Error('invalid event'))
     return
   }
@@ -91,6 +94,8 @@ Swarm.prototype._onAnnounceCompleted = function (params, peer) {
   this.complete += 1
   this.incomplete -= 1
   peer.complete = true
+  var id = params.type === 'ws' ? params.peer_id : params.addr
+  this.peers.set(id, peer)
 }
 
 Swarm.prototype._onAnnounceUpdate = function (params, peer) {
@@ -103,6 +108,8 @@ Swarm.prototype._onAnnounceUpdate = function (params, peer) {
     this.complete += 1
     this.incomplete -= 1
     peer.complete = true
+    var id = params.type === 'ws' ? params.peer_id : params.addr
+    this.peers.set(id, peer)
   }
 }