Hong Kong - A Hong Kong primary school teacher appeared in court Friday over allegations that he had sex with a pupil 280 times over a two-year period and persuaded her to have an illegal abortion.

Chu Chi-wah, 38, met the girl, now 17, while teaching her math and physical education from primary year three to six at the Catholic school she attended.

He began having sex with her in 2004. At the time she was 12 and had moved to a secondary school but was going to Chu's home daily for private tuition, a court report in the Hong Kong Standard newspaper said Friday.

Giving evidence via video in the trial of Chu, the girl said she had agreed to sex out of fear of her teacher.

"I didn't know how to refuse. Looking back, I was stupid and thought I can't just push him away," she said.

She estimated they had had sex 10 times a month for two years, on several occasions while fellow pupils were in another room.

She said she had tried to end the relationship but the teacher had threatened to chop her with a knife or kill himself, the Court of First Instance was told.

Chu is on trial charged with 12 counts of having sex with a child between January 2004 and June 2006, eight when she was aged under 13. He is also charged with conspiring to cause an illegal abortion.

The court heard that in the summer of 2004, the girl fell pregnant and Chu took her to a neighbour who was a gynaecologist who performed an abortion.

Eventually, the girl stopped seeing Chu but waited until last year to report him to the police when her 26-year-old boyfriend encouraged her to face the past.

Chu has denied all charges.