Operation Coldstore almost paralysed the Barisan because of the detention of its major leaders including Lim Chin Siong. However, remaining Barisan leaders did not give up their struggle. On 22 April 1963, Lee Siew Choh and remaining Barisan activists launched the "City Hall Battle". They marched from the Barisan's headquarter in Victoria Street to the steps of City Hall to protest the mass arrests in February and presented a petition to the Prime Minister in protest against the 'ill treatment' of the detainees. The protest was put down and seven party leaders including Lee Siew Choh were arrested.