Lebanese forces arrested two gunmen on Saturday after they opened fire on an army patrol near a Palestinian refugee camp in the north of the country, a security official said.

"Gunmen opened fire on an army patrol in Qobbeh," on the northeastern edge of the port city of Tripoli, the official said.

"There was an exchange of fire, but there were no injuries," he said, adding that two gunmen were arrested in the incident near the Beddawi Palestinian refugee camp.

Security concerns have mounted in Lebanon in the face of sporadic attacks on army posts and sectarian clashes between opponents and supporters of the Western-backed ruling majority.

On Thursday, the army defused a roadside bomb near a military base north of Tripoli and last month a soldier was killed in a blast at an army intelligence base in Abdeh, also in north Lebanon.

The latest violence comes as efforts to form a new national unity government are deadlocked over key portfolios, including the defense and interior ministries, despite an agreement last month by rival factions.(AFP)