WASHINGTON - HUMAN rights groups on Sunday blasted the Iranian police raid of Nobel laureate Shirin Ebadi's office in Teheran, calling it an 'unlawful' act and an attempt to silence activists.

'The unlawful raid by Iranian security forces on the Teheran rights group run by Nobel Laureate Shirin Ebadi on Dec 21, 2008, raises concerns of a broader attempt to silence Iran's human rights community,' the New York-based Human Rights Watch and the International Campaign for Human Rights in Iran said in a joint statement.

'The closure of DHRC (Human Rights Defenders Centre) is not just an attack on Shirin Ebadi and her Iranian colleagues, but on the entire international human rights community of which she is an influential and important member,' said Human Rights Watch executive director Kenneth Roth.

'The Iranian authorities should allow the centre to reopen and investigate why it was raided in the first place.' Ms Ebadi, who won the Nobel peace prize in 2003, was in the office during the raid.

Rights advocates said nearly 300 supporters of human rights had been invited to celebrate the 60th anniversary of the Universal Declaration of Human Rights at DHRC's office when the raid occurred.

'If Shirin Ebadi and DHRC cannot hold a simple event to celebrate the 60th anniversary of the Universal Declaration of Human Rights, then no Iranian citizen has any security to talk about or advocate for human rights,' said Hadi Ghaemi, spokesman for the International Campaign for Human Rights in Iran.

'This is a litmus test for the Iranian government's tolerance of human rights defenders, and its results show zero tolerance,' Mr Ghaemi said in a statement.

The two New York-based groups also raised concern of a wider crackdown, noting that 'in similar cases, Iranian authorities have frequently followed office raids and other harassment with arbitrary arrests and detention, often leading to prosecutions on dubious charges.'

The joint statement pointed to the case of Mohammad Sadiq Kaboudvand, who founded the Kurdistan Human Rights Organization and is serving a 10-year prison sentence 'solely for his activities as a human rights defender.'

According to reports from Iran's semi-official Mehr news agency, the centre was closed because it did not have an interior ministry permit to conduct its activities.

Political parties and associations must have such a permit to be legally recognised in Iran. -- AFP