Red Cross workers wheel a wounded Lebanese man into a hospital in Marjayoun. One Lebanese man was killed and another wounded when Isreali troops fired on them. -- PHOTO: AFP

A second Lebanese man was seriously wounded in the shooting.

An Israeli army spokesman said gunmen in Lebanon had opened fire on Israeli troops across the border on Sunday. He said the incident involved three drug smugglers who had crossed into Israel.

'The soldiers fired back and hit the gunmen,' the army spokesman said, adding the incident took place near the village of Ghajar.

The Lebanese security sources said there had been no gunfire from Lebanon. 'The Israelis opened fire unilaterally,' one of the sources said.

Unifil, the United Nations peacekeeping force in Lebanon, said it was investigating the shooting and urged restraint on both sides of the border.

Witnesses in Israel said the clash had ended and no more gunfire was heard.

Hizbollah, the Lebanese guerrilla group which fought a war with Israel in 2006, did not immediately comment on the incident. Its al-Manar television station reported the shooting, quoting its correspondent in the south.

Unifil troops evacuated one of the Lebanese men to hospital in the southern town of Marjayoun, where he died from his wounds, Unifil spokesman Yasmina Bouziane said.

'Unifil has launched an immediate investigation to ascertain the facts, looking into initial allegations of smuggling,' she said. 'Unifil's force commander, Major General Claudio Graziano, is in contact with senior officers on both sides urging them to show maximum restraint,' she added.

The Unifil force in south Lebanon was expanded in 2006 as part of a Security Council resolution that ended the 34-day war between Israel and Hizbollah, a group backed by Iran and Syria. -- REUTERS