Clashes between Yemeni youths divided over a power transfer deal that grants President Ali Abdullah Saleh immunity from prosecution left 35 people injured.
Stones and batons were wielded during the clashes in Change Square, epicentre of anti-regime protests since February and where a sit-in continues after Mr Saleh last month signed the deal by which he will quit in February 2012.
The attackers used sticks to destroy a podium set up by Shia rebels at the square and stoned the camp of hundreds of activists who reject the Gulf-brokered power transfer deal, witnesses said.
The Al-Islah party, which made up the largest opposition grouping during President Saleh's rule, signed the deal that provides immunity to the strongman, accused of corruption and whose forces and loyalists have killed hundreds nationwide.
The Gulf deal has been rejected by both the Shia rebels and young protesters.
