The US has condemned “in the strongest possible terms” a bomb attack on a bus carrying Israeli tourists in Bulgaria in which four people were killed and 27 injured.
White House press secretary Jay Carney said America “condemns such attacks on innocent people, especially children, in the strongest possible terms”.
He said President Barack Obama’s “thoughts and prayers are with the families of those killed and injured”.
Mr Carney said the US stands with the Israeli people and the people of Bulgaria.
He added that the Obama administration was working to learn all the facts in the case but the US’s “commitment to Israel’s security remains unshakeable”.
Israel has blamed Iran for the deadly blast in Burgas.