C313 Air-raid Alarm?

Weng!

It was as if it had come out from ancient times, and spread to every corner of the canyon. At this moment, no matter if it was Ye Yin and Guan Tingting who were in the forest, or the rest of the people on the abandoned road, all of them stopped what they were doing, and looked up at the sky in confusion!

Buzz! Buzz!

The loud sound rang out once more, as if it was produced by a great bell