![](http://www.ecns.cn/hd/2023/07/05/a71a020b1ace4b4cb00c418d9bafb7ad.jpg)
Police officers wearing anti-mosquito clothing spray insect repellent to each other during a patrol in Beiwan area Altay, northwest China's Xinjiang Uyghur Autonomous Region. (Photo: China News Service/Zhang Jiaxu)
Located on the north bank of the Irtysh River and bordered by Kazakhstan, Beiwan area is known as one of the four "mosquito kingdoms" in the world.
![](http://www.ecns.cn/hd/2023/07/05/6ea5b2b56c6840ab858848f988013a69.jpg)
Police officers wearing anti-mosquito clothing spray insect repellent to each other during a patrol in Beiwan area Altay, northwest China's Xinjiang Uyghur Autonomous Region. (Photo: China News Service/Zhang Jiaxu)
![](http://www.ecns.cn/hd/2023/07/05/a84cb92d629a4ba1a6066b2f12bfa663.jpg)
Police officers wearing anti-mosquito clothing spray insect repellent to each other during a patrol in Beiwan area Altay, northwest China's Xinjiang Uyghur Autonomous Region. (Photo: China News Service/Zhang Jiaxu)
![](http://www.ecns.cn/hd/2023/07/05/c0d8c425ddf04caaa32caacefa4f4126.jpg)
Police officers wearing anti-mosquito clothing spray insect repellent to each other during a patrol in Beiwan area Altay, northwest China's Xinjiang Uyghur Autonomous Region. (Photo: China News Service/Zhang Jiaxu)
![](http://www.ecns.cn/hd/2023/07/05/c4a5c7c2aa0247a59ff607e942dae8ad.jpg)
A police officer repels mosquitoes for a police dog during a patrol in Beiwan area Altay, northwest China's Xinjiang Uyghur Autonomous Region. (Photo: China News Service/Wang Youbo)
![](http://www.ecns.cn/hd/2023/07/05/01387bc6fad3470f80bc0a24aeb18a4f.jpg)
A police officer prays insect repellent to a police dog during a patrol in Beiwan area Altay, northwest China's Xinjiang Uyghur Autonomous Region. (Photo: China News Service/Wang Youbo)