An officer examines a suspected explosive device at Shanghai Pudong International Airport on Sunday after a man set off homemade bombs at a check-in counter, injuring four people. Lai Xinlin / For China Daily

Four people were injured in explosions at Shanghai Pudong International Airport on Sunday after a man threw homemade bombs at a check-in counter.

The incident happened at about 2:30 pm at Terminal 2, according to the Shanghai Airport Authority. Four passengers, including a Philippine national, were hurt in the blasts.

After throwing the devices, the suspect attempted to cut his throat and had to be hospitalized with a serious neck wound, police said.

Caixin magazine reported on its website that several witnesses said the man had thrown two bombs made from beer bottles and was preparing to take something out of a paper box when he was stopped.

One witness said two senior citizens were injured when they were hit by shards of flying glass in the second explosion.

Pudong New Area People's Hospital arranged for more than 10 doctors to treat the injured, Caixin reported.

"The area where the explosions took place was outside the security check zone, where travelers and their baggage are subject to security clearance," said Su Weiwei, an official with the Shanghai Airport Authority.

Police cordoned off the check-in counter, although only three flights were affected by the incident, the authority said.

Police are looking into a motive for the incident.

Security checks were upgraded soon after the incident and blastproof screens were placed at the entrances to the airport, Dragon TV reported.

wang_ying@chinadaily.com.cn