diff --git a/lib/src/client.dart b/lib/src/client.dart
index e7ad2e1..50ef0be 100644
--- a/lib/src/client.dart
+++ b/lib/src/client.dart
@@ -1708,8 +1708,12 @@ class Client {
   /// Sends an encrypted [message] of this [type] to these [deviceKeys]. To send
   /// the request to all devices of the current user, pass an empty list to [deviceKeys].
   Future<void> sendToDevice(
-      List<DeviceKeys> deviceKeys, String type, Map<String, dynamic> message,
-      {bool encrypted = true}) async {
+    List<DeviceKeys> deviceKeys,
+    String type,
+    Map<String, dynamic> message, {
+    bool encrypted = true,
+    List<User> toUsers,
+  }) async {
     if (encrypted && !encryptionEnabled) return;
     // Don't send this message to blocked devices.
     if (deviceKeys.isNotEmpty) {
@@ -1764,8 +1768,15 @@ class Client {
       "messages": Map<String, dynamic>(),
     };
     if (deviceKeys.isEmpty) {
-      data["messages"][this.userID] = Map<String, dynamic>();
-      data["messages"][this.userID]["*"] = sendToDeviceMessage;
+      if (toUsers == null) {
+        data["messages"][this.userID] = Map<String, dynamic>();
+        data["messages"][this.userID]["*"] = sendToDeviceMessage;
+      } else {
+        for (User user in toUsers) {
+          data["messages"][user.id] = Map<String, dynamic>();
+          data["messages"][user.id]["*"] = sendToDeviceMessage;
+        }
+      }
     } else {
       for (int i = 0; i < deviceKeys.length; i++) {
         DeviceKeys device = deviceKeys[i];
diff --git a/lib/src/event.dart b/lib/src/event.dart
index 1313eb8..0e8a01f 100644
--- a/lib/src/event.dart
+++ b/lib/src/event.dart
@@ -399,6 +399,7 @@ class Event {
         this.content["body"] != DecryptError.UNKNOWN_SESSION) {
       throw ("Session key not unknown");
     }
+    final List<User> users = await room.requestParticipants();
     await room.client.sendToDevice(
         [],
         "m.room_key_request",
@@ -406,7 +407,8 @@ class Event {
           "action": "request_cancellation",
           "request_id": base64.encode(utf8.encode(content["session_id"])),
           "requesting_device_id": room.client.deviceID,
-        });
+        },
+        toUsers: users);
     await room.client.sendToDevice(
         [],
         "m.room_key_request",
@@ -421,7 +423,8 @@ class Event {
           "request_id": base64.encode(utf8.encode(content["session_id"])),
           "requesting_device_id": room.client.deviceID,
         },
-        encrypted: false);
+        encrypted: false,
+        toUsers: users);
     return;
   }
 }