Brussels - The European Commission expressed "shock and dismay" Thursday at the shelling by Israel of a United Nations compound in the Gaza Strip and called for an independent probe into the incident.

"It is unacceptable that the UN headquarters in Gaza have been struck by Israeli artillery fire," said the EU's commissioner for humanitarian aid, Louis Michel.

"This is a very serious incident and there must be a full and independent investigation," he said in a statement.

UN officials on the ground said the compound was likely hit by white phosphorous shells during the fighting between Hamas and the Israeli military.

At least two key medical facilities and a two press buildings were also hit in separate incidents.

Some 700 Palestinians were inside the building, seeking refuge from the fighting, when it was hit, but the UN has since evacuated them to a nearby primary school.

Commissioner Michel offered his "full support" to the decision by the United Nations Relief and Works Agency (UNRWA) to suspend its operations following the incident.

The EU's executive arm in Brussels is the largest donor to UNRWA, with overall contributions totalling 113 million euros (148 million dollars) in 2008. (dpa)