diff --git a/engine/engine.go b/engine/engine.go
index d832aa2..18ef4f0 100644
--- a/engine/engine.go
+++ b/engine/engine.go
@@ -49,7 +49,7 @@ func BuildEngine(conf *Configuration) (*Engine, error) {
 
 func (engine *Engine) Loop() {
 	for {
-		engine.rooms.RLock()
+		engine.rooms.Lock()
 
 		engine.State.UpdatedAt = time.Now()
 		engine.State.ActiveRooms = 0
@@ -57,7 +57,7 @@ func (engine *Engine) Loop() {
 		engine.State.ActivePeers = 0
 		engine.State.ClosedPeers = 0
 
-		for _, pm := range engine.rooms.m {
+		for rid, pm := range engine.rooms.m {
 			pm.RLock()
 			ap, cp := 0, 0
 			for _, p := range pm.m {
@@ -73,11 +73,12 @@ func (engine *Engine) Loop() {
 				engine.State.ActiveRooms += 1
 			} else {
 				engine.State.ClosedRooms += 1
+				delete(engine.rooms.m, rid)
 			}
 			pm.RUnlock()
 		}
 
-		engine.rooms.RUnlock()
+		engine.rooms.Unlock()
 		time.Sleep(engineStateLoopPeriod)
 	}
 }