Gunmen attacked two army checkpoints outside the southern Lebanese city of Sidon, killing a soldier and wounding three others, the army said.
Four attackers were also killed in the clashes around the Mediterranean city on Sunday (local time), which was the scene of heavy fighting six months ago between the army and supporters of a Sunni Muslim cleric who backs rebels in neighbouring Syria's conflict.
One of Sunday's attackers killed himself and a soldier at a checkpoint in the Majdelyoun suburb to the northeast of the city when he blew himself up with a hand grenade, an army statement said.
Soldiers killed the two other checkpoint attackers, it said.
Less than an hour earlier, a man threw a hand grenade at the Awwali checkpoint at the northern entrance to Sidon, wounding two soldiers, the army said. He was also killed by soldiers.
There was no immediate claim of responsibility for the attacks, which follow days of fighting in June between the army and supporters of firebrand cleric Sheikh Ahmed al-Assir.
The violence in Sidon strained fragile sectarian relations across Lebanon and sparked fears that Syria-related clashes could eventually plunge the country back into civil war, like the one that raged from 1975 to 1990.
Majdelyoun neighbourhood is next to Assir's stronghold of Abra, which the army recaptured after fierce clashes in which dozens of his supporters were killed.
Assir himself disappeared during the fighting. Security sources said last month Lebanese authorities identified one of the suicide bombers who attacked the Iranian embassy in Beirut on November 19 as a Palestinian with links to the fugitive sheikh.