HONG KONG (AFP) - The Filipina mother of a teenager in Hong Kong has been charged with neglect after her daughter plunged to her death from an upmarket apartment block.

Police said there was "no suspicious element" in the 15-year-old girl's fatal fall, but arrested both her parents on suspicion of "ill-treatment or neglect of a child or a young person".

Her father, 58-year-old Nick Cousins, is the managing director of the Hong Kong office of British multinational Jardine Lloyd Thompson (JLT), one of the world's leading insurance brokers.

The girl's mother is a 53-year-old Philippine national, the consulate in the Hong Kong said, adding that they were still ascertaining her identity.

She is a former domestic helper, according to local media.

Cousins has been released on bail but the teenager's mother was charged late on Wednesday on the "ill-treatment and neglect" count.

She was also charged with "overstaying" in Hong Kong and will appear before magistrates on both charges Thursday.

The 15-year-old plunged from the 21-storey apartment block in Repulse Bay early Tuesday morning, police said.

Her younger sister was initially taken to a children's home, and the police are seeking a protection order for her.

However, she was released back into her family's care late Wednesday while the social welfare department produces an assessment report on the case.

"The child will be taken care of by her family during the adjournment period," a department spokesperson said.

The teenager's mother has also been accused of overstaying her visa, while Cousins was accused of aiding or abetting the overstay. The couple were not married, police said.

JLT confirmed Cousins had lost his elder daughter "in tragic circumstances".

"We are giving Nick our full support through this difficult time and he will be on extended compassionate leave until further notice," a statement said.

Police said the teenager was pronounced dead at the scene after a security guard heard a loud noise and she was found lying on the ground.

"We learned that the subject was probably upset about some daily life issues," a spokesman said.

Local media reported that she had locked herself in a bathroom before her death.

Residents of the Repulse Bay neighbourhood expressed their dismay.

"I was shocked because she (the teenager) would always say 'Hi' to me. She was friendly," said a domestic helper who works in the same building.

The South China Morning Post, citing a police source, said that the 15-year-old and her younger sister had been educated at a private tutorial centre and had never gone to school. Their births had also never been registered, the report said.

It said their mother had been working as a domestic helper in Hong Kong from 1990 and began living with Cousins in 1994.