MSF said it was "appalled and saddened by the killing of our colleague Hussam Al Loulou by an airstrike on the morning of 1 April".

"Our colleague Hussam was killed along with hundreds of others across the Gaza Strip since the resumption of attacks by Israeli forces on 18 March," MSF said.

The 58-year-old watchman at MSF's urgent care unit in Khan Yunis was killed along with his wife and 28-year-old daughter in the "horrendous attack" southwest of Deir Al Balah in central Gaza, MSF said.

He was the eleventh MSF worker killed in Gaza since the start of the war there began 18 months ago and the second since the collapse last month of a short-lived truce.

Hundreds of aid workers have been killed during the war in Gaza, which erupted after Hamas's deadly attack inside Israel in October 2023.

The health ministry in Gaza said 1,249 people have been killed in the Palestinian territory since Israel resumed intense bombing on March 18, bringing the overall death toll since the war began to 50,609.

MSF hailed Loulou for his "selflessness, humility and genuine care for those around him", adding that he was survived by two sons.

"We strongly condemn his killing and call yet again for the immediate restoration of the ceasefire and protection of civilians," the organisation said.

"This bloodshed needs to end."