A large explosion rocked a Palestinian camp in the southern Lebanese port city of Tyre on Friday night causing a number of deaths and injuries, state media reported.
A Palestinian source inside the camp said at least 12 people had been injured and there were an unknown number of fatalities.
The explosion took place at a Hamas weapons depot in the Burj al-Shemali camp and a judge had ordered security forces to launch an investigation, the state-run National News Agency reported.
Shehab News Agency, seen as close to Hamas, quoted a Palestinian source as saying the explosion was caused by the ignition of oxygen canisters stored for use in fighting the COVID-19 pandemic.
Hamas maintains a presence in a number of Palestinian camps in Lebanon.
The surrounding area had been evacuated and rescue crews had deployed, the Palestinian source said.
Videos from the scene shared by local media show a number of small bright red flashes above the southern city, followed by a large explosion and the sound of glass breaking.
A number of armed Palestinian factions, including Hamas and the Fatah Movement, hold effective control over roughly a dozen Palestinian camps in the country, which Lebanese authorities by custom do not enter.