Fighters take part in a funeral procession for Hamza Ibrahim Shahin, a member of the Hamas movement ruling in the Gaza Strip, in the Burj al-Shamali camp for Palestinian refugees near the southern Lebanese coastal city of Tyre on December 12, 2021. AFP
Hamas official Raafat al-Murra said militants from the rival Fatah movement "shot at the funeral procession" of a Palestinian killed in a blast Friday at the Burj al-Shemali camp, outside the port city of Tyre.
Six people were wounded, he said.
A camp resident told AFP an armed clash followed the shooting and that elements of both Fatah and Hamas had been deployed.
An electrical short circuit in a store containing oxygen supplies for Covid patients caused Friday's blast, Hamas had said, denying media reports that an arms depot blew up.
The explosion blackened the walls and shattered windows of a nearby mosque.
"The fire caused damage to property but the impact was limited," Hamas said, without detailing casualties.
According to a Palestinian official, one man died of his injuries from Friday night's explosion, which also left a few people wounded.
Officially, Lebanon hosts about 192,000 Palestinian refugees, most of whom live in the country's 12 camps, according to the United Nations Relief and Works Agency (UNRWA).
By longstanding agreement, the Lebanese army does not enter the camps, leaving security inside to Palestinian factions.
Hamas and Fatah, the secular party led by Mahmud Abbas, have been at odds since 2007 when the Islamists seized Gaza after a week of deadly clashes.
Though based in Gaza, Hamas operates branches elsewhere in the Middle East including Lebanon.