Switzerland has condemned "unambiguously" Israel's shelling of a United Nations building and a hospital in Gaza city.
"Attacks against humanitarian organisations, hospitals and medical personnel constitute violations of international humanitarian law," said a foreign ministry statement released on Thursday.
The statement added that Israeli fire had also hit a depot belonging to the Palestinian Red Crescent Society and press agency offices.
It repeated Switzerland's call to both sides to cease hostilities in the Gaza Strip immediately, and called again for an independent inquiry commission to investigate allegations of breaches of international law in the conflict zone.
During Thursday's shelling, three employees of the UN Relief and Works Agency (UNRWA), were injured and large quantities of aid stored there were destroyed. UNRWA is responsible for looking after the needs of Palestinian refugees.
Israeli Prime Minister Ehud Olmert said troops had opened fire on Hamas militants in the location, and he apologised for the damage. The head of UNRWA in Gaza described the Israeli claim as "total nonsense".
In the attack on the Quds hospital, a fire broke out after a shell hit the pharmacy, eye-witnesses said.