Kenyan legislators Thursday exchanged blows forcing parliament to adjourn the debate on proposed changes to security laws which the government says will help fight terrorism but which critics say are meant to silence dissent by curtailing civil liberties.

Opposition legislators threw the papers on the floor and chaos erupted in which government supporters hit and tore the clothes of opposition senator Johnston Muthama, who was seated in the public gallery. The ruckus was broadcast on national television.

There was a heavy police presence in the city center which was increased following the fracas in parliament. Police fired warning shots in another part of the capital where pro-opposition youths had blocked the road.

President Uhuru Kenyatta has urged parliament to pass the proposed changes saying they will strengthen security following a series of terrorist attacks blamed on the Somali Islamic extremist group al-Shabab.

Nine western governments, including the United States and Britain have urged Kenyan legislators to respect human rights while enacting the proposed changes.

The laws have been opposed by the media, human rights groups and the main opposition coalition which say they will restrict freedoms. Opposition legislators say if enacted the new laws will infringe on civil liberties reminiscent of the autocratic regimes of Kenya's first two presidents; President Jomo Kenyatta — the father of Kenya's current president — and Daniel Arap Moi.

Among the changes government has proposed in the security laws is a fine of $56,000 or a three-year jail-term or both on journalists whose stories are deemed to undermine terror investigations, a similar fine for media which publish pictures of terror victims without the permission of the police.

The new laws also propose to give the president powers to fire and hire the police chief and intelligence chief.