Tran Khai Thanh Thuy and her husband were still in custody and not allowed to meet with family, a relative told AFP.

An officer at Hanoi's Dong Da district police said there was nobody with Thuy's name being held in his area.

Foreign diplomats said she was initially stopped on Thursday while on her way to the northeastern port city of Haiphong where a trial began for six dissidents charged with hanging pro-democracy banners and conducting other allegedly anti-state activities.

Thuy was "roughed up" by police on Thursday and initially released from detention, only to be held again that night, one diplomat said.

Lao Dong newspaper on the weekend quoted Vu Cong Long, head of Dong Da district police, as saying Thuy had been arrested on a charge of intentionally inflicting injury. On conviction, the charge can lead to imprisonment.

The report said Thuy's husband allegedly struck a man in the face with a motorcycle helmet during a parking dispute in Hanoi on Thursday. Thuy then allegedly threw a brick which hit the man in the face, the report said.

In Haiphong on Friday, the six dissidents were sentenced to up to six years in prison under Penal Code Article 88, which rights activists say criminalises peaceful dissent.

Thuy was herself previously arrested under Article 88 but was convicted on a lesser charge and spent several months in prison.

Agence France Presse - october 12, 2009