A Kenyan parliamentary debate on contentious plans to change security laws had to be adjourned after legislators exchanged blows.

The government says the proposals will help fight terrorism but critics say they are meant to silence dissent by curtailing civil liberties.

Opposition legislators threw the papers on the floor today and government supporters hit and tore the clothes of opposition senator Johnston Muthama, who was seated in the public gallery.

The exchanges were broadcast on national television.

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 US and Britain, have urged Kenyan legislators to respect human rights while enacting the proposed changes.