Hundreds of students chanting "Death to America" protested Pakistan's support for the US-led war on terror, as the government vowed Tuesday that security forces would show "no leniency" in the escalating conflict with Islamic militants. In the latest violence, a missile strike near the Afghan border destroyed a suspected militant hide-out and killed 12 people inside, local intelligence and government officials said. In the southern city of Karachi, two police and three militants died in a fierce gunbattle, said Arif Ahmad Khan, the provincial home secretary. Khan said the dead included an Uzbek and Qasim Turi, a local militant leader wanted for his ties to the banned Sunni Muslim militant groups Lashkar-e-Jhangvi and Jundullah, blamed for several attacks in Karachi - including a June 2004 assassination attempt on the regional army commander. Khan would not say who the slain Uzbek was and only said officers were still investigating.