An Israeli military attack on the largest hospital in southern Gaza killed two people, injured several, and sparked a large fire, according to the enclave’s Ministry of Health.

The attack on Sunday night hit the surgical building of Nasser Hospital in the city of Khan Younis, the ministry reported. The attack came just days after the facility was overwhelmed with the dead and wounded, as Israel resumed its war in Gaza with a surprise wave of air raids last week.

Among those killed on Sunday was a 16-year-old boy who had undergone surgery two days earlier. Also killed was Ismail Barhoum, a member of Hamas’s political bureau who was receiving medical treatment at the hospital, Hamas said in a statement.

Israel’s military confirmed the attack, stating it had hit a member of Hamas. Israeli officials have repeatedly blamed civilian casualties on the armed Palestinian group that governs Gaza, arguing it deliberately operates in densely populated areas.

Like other medical facilities across Gaza, Nasser Hospital has suffered damage from Israeli raids and air attacks throughout the conflict.

Israeli forces have killed more than 600 people since resuming the assault on the enclave, including dozens within the past 24 hours, according to Palestinian health officials.

On Sunday, the official death toll in Gaza since the beginning of the war exceeded 50,000, according to the Health Ministry. However, many experts believe this figure is likely a far undercount of the actual number.