|The attack happened on the same day UNIFIL was commemorating the International Day of UN peacekeepers [AFP]
At least six Italian peacekeepers have been wounded in southern Lebanon after an explosion blew up a UN vehicle they were travelling in, security sources said.
Friday's explosion occurred on a highway leading to the southern port city of Sidon, the sources added. They, however, did not confirm initial reports that said one of the peacekeepers had been killed.
The army sealed off the area with yellow tape and was keeping journalists away. But a blackened white United Nations Interim Force in Lebanon (UNIFIL) jeep could be seen, its top and left side destroyed.
The powerful explosion caused a large crater and broke the cement barrier on the highway.
The attack happened on the same day the UNIFIL was commemorating the International Day of United Nations Peacekeepers to honour colleagues who lost their lives in the line of duty.
UNIFIL's deputy spokesman, Andrea Tenenti, told Al Jazeera there were "some reports of casulaties", adding that "teams" had been sent to the location to gather more information.
Al Jazeera's Zeina Khodr, reporting from the main highway linking Beirut, the capital, to Sidon, said there had been no claim of responsibility.
"I have been speaking to officials from the UN peacekeeping operation; they're refusing to blame any party ... until investigations are completed," she said.
Ban Ki-moon, the UN secretary-general, condemned the attack and said "it is all the more deplorable because today is the International Day of United Nations Peacekeepers".
"We are still receiving details, but it is already clear that a number of UN peacekeepers have been wounded," he said.
Lebanon's Prime Minister-designate, Najib Mikati, also condemned the attack in a phone call to the UN special co-ordinator for Lebanon, Michael Williams.
Franco Frattini, the Italian foreign minister, praised the UNIFIL mission, saying it made a "decisive contribution to the stability of one of the most sensitive Middle Eastern areas".
UN peacekeepers in Lebanon have previously come under attack.
The last attack was in January 2008, when a roadside bomb struck a UN vehicle travelling along the coastal highway south of Beirut, lightly wounding two peacekeepers.
The deadliest attack was in June 2007, when six peacekeepers - three of whom Spaniards and others Colombians - were killed after a bomb hit their armoured personnel carrier near the Israeli border.
There have been 292 fatalities of peacekeepers serving with UNIFIL since its establishment in 1978.
The 13,000-strong force, of which Italy forms the largest contingent, was expanded after a 2006 war between Israel and the Lebanese Shia group Hezbollah.