Several explosions shook a Palestinian refugee camp in southern Lebanon on Friday night. The nature and causes of the blasts were not immediately clear. Lebanon’s state-run National News Agency had reported that arms stored for Hamas exploded on Friday in the Burj Shamali camp, killing and injuring a number of people. Locals said at least one person had died. Videos from the scene shared by local media show a number of small, bright-red flashes above the southern city of Tyre, followed by a large explosion and the sound of glass breaking. Multiple blasts during a fire are often called "secondary explosions" by security analysts and sometimes point to the presence of explosives, but this is not always the case. Ambulances rushed to the scene in the Burj Shamali camp, residents told The Associated Press. Lebanon’s state-run National News Agency said there had been casualties, while a Palestinian source inside the camp told Reuters that at least 12 people had been injured. The NNA reported that a judge had ordered security forces to launch an investigation into the explosion. 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. The NNA said the army had cordoned off the area, preventing people from entering or leaving the camp. Hamas denied reports that its weapons were involved in the blast. In a statement issued on Saturday, the group said the explosion was caused by a short circuit in a warehouse containing oxygen cylinders, and that there had been no fatalities. Hamas said the oxygen bottles and containers of detergents stored at the camp were to be distributed as part of its aid work in the camp. “Hamas condemns the misleading media campaign and the spread of false news that accompanied the incident,” the militant group said in its statement. Lebanon is home to tens of thousands of Palestinian refugees and their descendants. Many live in the 12 refugee camps that are scattered around the small Mediterranean country. <i>Agencies contributed to this report</i>