At least four guards have been killed in a shooting attack at Karachi international airport in Pakistan Sunday night. Officials say at least eight gunmen were involved. They targeted the cargo and V.I.P. Area of the airport, and they reportedly hurled grenades in addition to exchanging gunfire. Officials say the fighting is ongoing. Witnesses said they saw smoke rising from the airport and one television showed footage of a fire near a plane. Karachi is Pakistan's busiest airport.