A 15-year-old accused of knocking down a woman he insists he was just trying to help up after she had been hit by an electric car remained in police custody on Monday.

The police took away the boy, whose surname is Zhang and who is a freshman in a vocational school, for questioning at around 5 pm on Sunday, Wuhan Evening News reported. Zhang said the accident occurred while he was in a car on his way to an avenue in Wuhan, the capital of Hubei province. He said he saw a car that was about five or six meters away from him hit the woman and drive away.

"I immediately stopped my car and picked her up," Zhang was quoted as saying. He said the woman, whose surname is Song, thanked him.

By the time the police had come to the site, though, Song was blaming Zhang for the accident, Zhang said.

Song suffered a fracture to her left leg and was sent to the hospital for treatment.

Because there was no witness of the accident, the police said on Monday they would look at surveillance videos to try to learn what had truly happened.

Chen Ji, the director of Wuhan Traffic Safety Administration's publicity department, said an investigation into the accident had produced no final results by Monday afternoon.

Zheng Lei, a student pursuing a doctorate in law at Peking University, said such incidents happen because society lacks a basic sense of trust.

On Thursday, a 2-year-old girl was run over twice by vehicles in Foshan, a city in Guangdong province, and then ignored by 18 passers-by before being helped.

Zhang Tingyin, a professor with the Party School of the Henan Committee of the Communist Party of China, said both would-be rescuers and victims have responsibilities they must meet when accidents occur.

Victims should have the moral sense to be grateful for the help offered them, while those who want to give others a hand should have some basic knowledge about proper rescue techniques.