"She is so young and has yet to have babies, so we only amputated her legs, but if things get worse, I'm afraid her bottom will have to be removed, too," Cao said.

Her pulse and blood pressure are improving, but she is still in critical condition and the risks of infection after the operation remain high, Cao said.

"Her heroic deeds are so touching. We will do our utmost to save her," Cao said.

Zhang's accident has shocked and saddened her family, colleagues and students.

Zhang's father has yet to accept what has happened to his daughter.

"I am her rock, but she is my world," her husband Li Ziye said in an interview with Xinhua.

After the incident, many students and their parents went to the hospital, offering to donate their blood and money to Zhang, said Wang Yuwen, Zhang's colleague.

"She is like a mother figure to me, and when I was with her, I felt warm in my heart," said Yan Hongyi, one of Zhang's students.

"I was very sad that my teacher was injured, but I am not surprised that she would risk her life to save others," Yan said. "She once protected us from a bicycle that was about to hit us back in 2009."

"Zhang has been donating 100 yuan each month to a boy in her class for three years now. I feel that I have so much to learn from her," Wang said. (100 yuan is equal to 15.9 US dollars.)

The driver, surnamed Xiao, has been detained.

Xiao said she knew the bus's brakes were not working well, and after she started the engine, she got distracted talking to people on the bus and her leg accidentally pushed the gearshift, said Zhang Jiandong, an official with the Jiamusi Traffic Police.

Zhang Lili, a 29-year-old middle school teacher in Northeast China's Heilongjiang province, is lying on a hospital bed in the Intensive Care Unit on May 12. She was run over and lost both of her legs after pushing two students out of the way of an oncoming bus. [Photo/Xinhua]