The British government said on Monday it was “urgently” investigating media reports that a British aid worker has been killed in Gaza.

“We are aware of the reports of the death of a British national in Rafah and are urgently looking into them,” a spokesman for the Foreign Office said.

Sky News television, citing unidentified sources, said the aid worker was killed on Sunday in an Israeli airstrike in the southern city of Rafah, which straddles the border with Egypt.

The news came as Israel observed a temporary unilateral truce in most of the Gaza Strip.

“I’m extremely concerned about these reports and we are doing everything we can to get to the bottom (of them) and find out exactly what has happened,” British Prime Minister David Cameron said, according to Sky News.

“I don’t want to say anything before we’ve been able to do that, but this only reinforces the need for an immediate, unconditional humanitarian ceasefire observed properly by both sides,” he added.

“This slaughter, this killing has got to end.”

Times of Israel Staff contributed to this report