A big fire tore through a camp for Syrian refugees in Lebanon’s Bekaa Valley on Sunday (July 2), killing three people, Lebanese media reported.

Flames and thick clouds of black smoke rose from the site near the town of Qab Elias, around an hour’s drive east of Beirut, and at least one explosion was seen in footage broadcast by Lebanon’s MTV.

A security source said the cause of the fire was not immediately known.

Lebanon is hosting at least one million registered Syrian refugees, many of them living in informal tented settlements scattered around the country.