In Pakistan, gunmen attacked a military base in Karachi killing at least 11 soldiers. Officials said, the well-armed attackers set off explosives and have been fighting gun-battle with navy personnel at the Mehran naval aviation base. The gunmen are now holding hostages, including Chinese military personnel. No group has claimed the responsibility but Pakistani Taliban have vowed to avenge the killing of Osama Bin Laden by US special forces on the second of this month. According to officials, militants stormed three hangars housing aircraft at the Mehran base last night. Interior Minister Rehman Malik said security forces have been able to confine them to one building and an operation is underway either to kill or capture them. Navy commandos and marines have launched a counter assault. Dozens of heavily armed army reinforcements have also arrived to provide cover. Ambulances with sirens wailing stood outside the gate of the compound which was sealed soon after the attack began. They were joined by dozens of TV satellite trucks and journalists. The base is located next to the Shahrah-e-Faisal – Karachi's main road and many interested onlookers stopped their vehicles to find out what was happening. In the distance, flames could be seen in the horizon beyond the perimeter wall.