Sniffer dog a boon for drug busts at Qingdao airport

"Zhongyang likes seeking fun, and training seems never to be boring and difficult for him," said his handler Ren Haiqing, a 48-year-old customs officer.

"However, Zhongyang sometimes is too naughty to obey the rules," Ren added, smiling.

As an encouragement or a reward, Ren throws him a rolled-up towel and plays his favorite game, tug-of-war, which, as always, Ren will let Zhongyang win.