A father in Nanjing, the capital of Jiangsu province, asked police to detain their son after they found he was using drugs, Yangtze Evening News reported on Wednesday.

The parents recently noticed their 15-year-old son was behaving strangely when he returned home after leaving a month earlier, and tried to ask him the reason. The father then reported to the police that he knew his son took drugs during his absence from home. With information from the teenager, police caught a person suspected of selling drugs to the boy and two others suspected of taking drugs. Police reminded all parents to pay more attention to their children and help them stay away from drugs.