Multiple aid workers were killed after a bus was attacked in Gaza on Wednesday night, according to a US-backed humanitarian aid organization which accused Hamas of carrying out the assault.

The group, which has been harshly criticized by the U.N. and other aid providers, said at least five people had died in an attack on one of its buses.

Hamas "brutally attacked" a bus carrying the Gaza Humanitarian Foundation (GHF) staff to a distribution site near the southern city of Khan Yunis on Wednesday night, killing at least five, the US-backed charity said.