ISLAMABAD - Opposition political parties lashed out at the government in a fiery session of National Assembly on Tuesday over the gruesome killings of Minhaj-ul-Quran protesters in Lahore.While the opposition was all praise for Prime Minister Nawaz Sharif for taking terrorists head-on by giving green signal for military offensive on Monday, the news about killing of eight people in clashes between Punjab police and supporters of religious scholar Tahirul Qadri invited the ire of opposition who blamed Chief Minister Shahbaz Sharif for letting his elder brother down at a time when the government needed massive support.And within minutes, the house was reduced to PML-N members after joint opposition staged a walkout to register protest at the brutal killings in Lahore, the home constituency of Prime Minister Sharif."I have already warned the government to be extra careful so that democracy prevails in country. But now I am sure that Chief Minister Sharif poses bigger threat to Prime Minister Sharif than any other," said Opposition Leader Khurshid Shah, who had assured all-out support to the premier on Sunday about the military operation in North Waziristan."Everybody knows about the motives of the Canadian national but I wonder as to what was the need to break up his supporters? Again I will say that the younger brother of our prime minister poses threat to the system," the PPP leader maintained.MQM lawmaker Farooq Sattar, who until Monday was singing songs of the ruling PML-N for its determination to flush out terrorists from the country, was a firebrand opponent of the ruling party on Tuesday in National Assembly staging walkout in protest against the Lahore incident.The ruling party seemed to be in more trouble to explain the killing in Lahore in absence of Interior Minister Chaudhary Nisar Ali Khan, who is known for pacifying a tense situation. Instead Federal Minister for Planning and Development Ahsan Iqbal, who came to know about the tragic event through television, came to the rescue of Punjab government assuring probe into the event but his speech did not work resulting in more anger from the opposition.Even the usually reserved Aftab Khan Sherpao was an outspoken lawmaker on Tuesday pointing finger at PML-N for 'digging its own grave' and boasting its majority in the lower house."Our prime minister is living in a fantasy that nothing will happen to the government for being in majority in National Assembly. This will not work in the longer run. Nobody can have a solo flight in the current situation," Sherpao said showing anger at the killing of people in Lahore.Railway Minister Kh Saad Rafique outside the assembly building was lambasting MQM's chief Altaf Hussain and Tahirul Qadri at a time when the PML-N stalwart was expected to cool down the already heated atmosphere.PTI's lawmaker and former federal minister Ghulam Sarwar Khan told the house that the ruling PML-N was in a fix over how to react in a situation and cool down tempers of opposition when its own government in Punjab was under fire for opening fire on peaceful protesters.Speaker Ayaz Sadiq instead of listening to the advice of Khan disconnected his mike for consuming more time, triggering the PTI leader from Taxila to stage a walkout in protest that was followed by other party lawmakers.Perhaps PPP leader and former speaker of the house Dr Fehmida Mirza cooled tempers of members by touching a different topic and revealed that cancer was the major cause of deaths in Pakistan, calling for a national policy to control the disease.This news was published in The Nation newspaper. Read complete newspaper of 18-Jun-2014 here.