When the onetime director of a Gaza Strip hospital was killed by an Israeli airstrike, he joined a growing list of prominent Palestinian doctors who have died during 21 months of war that has devastated the territory’s health system.

The strike in Deir al-Balah in the central Gaza Strip came as Israeli and Hamas negotiators hold talks with mediators in Qatar over a proposed 60-day ceasefire and hostage release deal aimed at building agreement on a lasting truce.