diff --git a/app/controllers/activities_controller.rb b/app/controllers/activities_controller.rb
index 930caf24843a..14a9af48b6b6 100644
--- a/app/controllers/activities_controller.rb
+++ b/app/controllers/activities_controller.rb
@@ -45,20 +45,18 @@ class ActivitiesController < ApplicationController
 
   accept_key_auth :index
 
+  rescue_from ActiveRecord::RecordNotFound do |exception|
+    op_handle_warning "Failed to find all resources in activities: #{exception.message}"
+    render_404(message: I18n.t(:error_can_not_find_all_resources))
+  end
+
   def index
     @events = @activity.events(from: @date_from.to_datetime, to: @date_to.to_datetime)
 
     respond_to do |format|
-      format.html do
-        respond_html
-      end
-      format.atom do
-        respond_atom
-      end
+      format.html { respond_html }
+      format.atom { respond_atom }
     end
-  rescue ActiveRecord::RecordNotFound => e
-    op_handle_warning "Failed to find all resources in activities: #{e.message}"
-    render_404 I18n.t(:error_can_not_find_all_resources)
   end
 
   def menu
diff --git a/spec/controllers/activities_controller_spec.rb b/spec/controllers/activities_controller_spec.rb
index f180975dd12f..eecafbf411d9 100644
--- a/spec/controllers/activities_controller_spec.rb
+++ b/spec/controllers/activities_controller_spec.rb
@@ -101,6 +101,14 @@
         expect(response).to be_successful
         expect(response).to render_template "index"
       end
+
+      describe "with not existent user_id" do
+        it "renders 404" do
+          get "index", params: { project_id: project.id, user_id: 123123123 }
+          expect(response).to have_http_status(:not_found)
+          expect(response).to render_template "common/error"
+        end
+      end
     end
 
     describe "without activated activity module" do