The father of the missing baby, identified as Mr Xu, said he left the child in the vehicle before entering a supermarket because he was afraid the supermarket would be too cold for the baby, China National Radio said. Xu told the radio station he left the car engine running and doors unlocked before leaving the vehicle.

Police launched a city-wide manhunt, involving 3,500 officers, after they received Xu’s report while radio stations in the city have advised the public to pay attention to suspected cars, the report said.

“I beg you to keep my child safe. Do not harm my child,” Xu said in a radio broadcast at 8.30am. Police and radio hosts also repeatedly broadcast an appeal to the vehicle thief to stop fleeing and keep the child safe.

Changchun residents also have participated in the large-scale manhunt, the report said. As of 8.44am, dozens of private car owners and taxies have volunteered to help search for the missing vehicle, and the number of volunteers is rising. Official weibo accounts have published the news and it has been reposted on major internet portals in the afternoon.

Changchun police have set up inspection points on major roads and a wider-area alert has been sent out in case the car thief has left the city.