Springer Spaniel Xingchen focuses on handler Chen Zhonghuang while on duty at a metro station in Hangzhou. [Photo/WeChat account: hzfm918]

A police dog called Xingchen has become an online sensation after being spotted on duty in the Hangzhou Metro Line 1 — located in Hangzhou, capital of East China's Zhejiang province — standing tall and alert beside his handler.

With his proud posture and serious gaze, many netizens joked: "He knows he looks cool!"

But according to handler Chen Zhonghuang from the Hangzhou public security bureau's metro SWAT unit, the 7-year-old Springer Spaniel isn't being smug — he's simply focused. Xingchen is trained to detect explosives and flammable substances like fireworks and gasoline. When patrolling, he stays close, watching for commands.

Off duty, Xingchen enjoys downtime at the police dog base, where 17 active police dogs train daily to help maintain subway safety — either through explosive detections or checking for suspects. Despite the intense work, Xingchen is a relaxed and cheerful pup once off the clock.

These silent "warriors" work year-round, their discipline and skill rooted in relentless training to respond swiftly to emergencies in the metro.