Two military transport planes landed at the Beirut airport on Friday, bringing foreign military aid to help the Lebanese army fight Islamic militants, security officials said. The development comes after the United States said it would rush supplies and ammunition to Beirut. Lebanese officials would not disclose where the military planes came from - whether directly from the United States or from US military depots in the Middle East. Late Thursday, a United Arab Emirates air force plane also arrived with supplies. The military refused comment on the airlift, a sensitive issue in this troubled country. A Pentagon official said earlier Thursday that the US was rushing ammunition and other equipment to the Lebanese army in a military airlift of eight planes. But local Lebanese television stations said even more planes were expected to arrive. A US military official at the Pentagon said the Lebanese government had asked the United States several days ago to expedite the shipment of a broad range of equipment and ammunition that was already in the pipeline for delivery to the country. The Beirut government subsequently told the US it needed the ammunition right away, a security official said. In response, the US sent the first planes loaded largely with ammunition, said the official, who requested anonymity because of the sensitivity of the issue. All the materials en route had previously been requested, the agreements were already in place, and they were in the delivery process, the official stressed. The official did not know exactly how much ammunition was included in the transports Friday. The planes, flying over the city in the morning, were spotted by many residents. Western-backed Prime Minister Fuad Saniora vowed Thursday to wipe out the Islamic militants barricaded inside the Palestinian refugee camp near the northern port city of Tripoli, raising prospects that the army will either storm the camp or dig in for a long siege to force its surrender. Sporadic gunfire was exchanged overnight into Friday, marring a two-day-old truce that held as the military surrounded the Nahr el-Bared Palestinian camp. The militants from the al-Qaida-inspired Fatah Islam militant group - estimated in the hundreds - have been holed up inside the camp since Sunday. The government has given them an ultimatum to surrender or face a military assault.