A New Zealand teen was forced to marry her boyfriend's father and consummate the marriage after the groom gave her parents a pig and some mats as a dowry, according to a report Sunday.

The Sunday Star Times said the Tongan girl, aged about 17, was allegedly assaulted after fleeing to her boyfriend -- reportedly her new husband's son -- on her wedding night.

The mother is also charged with assaulting her daughter twice over the marriage issue.

The police became involved when the teenager sought a restraining order against her mother.

The girl did not want to marry the man but she was obliged to honour an agreement made between the families, which included a pig and mats as a dowry, a source told the newspaper.

On her wedding night, the girl ran away to her boyfriend.

It was then that she was allegedly assaulted, abducted and taken back to the matrimonial home to perform her duties as a wife, the report said.

Neither the girl nor her husband could be reached for comment but her mother told the newspaper: "My family's problems are gone... I don't want to say anything."