Beijing stepped up its attack on the Dalai Lama yesterday, saying the exiled Tibetan spiritual leader was spreading rumours to hide his 'guilty conscience'. Ministry of Foreign Affairs spokeswoman Jiang Yu said the truth about the March 14 riots in Lhasa was obvious and there was irrefutable evidence, which would 'not be changed by hearsay and rumours [spread] by the Dalai Lama', according to a statement on the ministry's website. 'It can only prove that he was acting out of guilty conscience to find excuses not to take responsibility for the riots in Lhasa,' the statement said. Ms Jiang was responding to a question about the Dalai Lama's remarks on Saturday that Beijing had disguised its troops as monks to give the impression that Tibetans were instigating the riots. The Dalai Lama had said: 'In one picture we see a [monk] holding a sword, but it is not a traditional Tibetan sword. We know that a few hundred soldiers have been dressed like monks.' The ministry's harsh words were in stark contrast to Premier Wen Jiabao's mild appeal on Sunday when he asked the Dalai Lama to 'use his influence to stop violent activities in Tibet '. Beijing has consistently accused the Dalai Lama and his supporters of instigating protests that began peacefully on March 10 in Lhasa but escalated into violent riots on March 14. The protests also spread to neighbouring Tibetan-populated areas such as Sichuan, Qinghai and Gansu . Beijing said 18 civilians and one police officer were killed in the Lhasa riots and more than 800 were injured. The Tibetan government-in-exile said 140 people died. A Xinhua report yesterday said Lhasa police had arrested 414 people, the same figure given last week, for their involvement in the riots. They also detained five suspects for arson attacks that killed 12 people, including an infant, the report said. Beijing made no mention of protests at the Ramoche monastery and the Jokhang Temple in Lhasa on Saturday when foreign diplomats were in the city on a visit tightly controlled by the central government.