At least five Palestinians have been killed after an Israeli airstrike hit a building at Nasser Hospital in southern Gaza, an official from the Hamas-run Civil Defence agency has told the BBC.

Eyewitnesses said that a single missile, fired from a warplane that briefly flew over the area, struck a building housing the hospital’s surgical wards and intensive care units. Twenty others were injured, the civil defence spokesman said.

A surgeon is reported to be among those who were killed during the strike early on Thursday.

The Israeli military says it struck a senior Hamas member and other militants who were using the hospital “as a command center for military and terrorist activities”.

In a joint statement, the Israel Defense Forces (IDF) and Israel Security Agency (ISA) said that they strongly condemn Hamas exploiting “civilian and medical infrastructure for military purposes”.

They added that “steps were taken to mitigate harm to civilians, including the use of precision munitions and aerial surveillance”.

Under international law, hospitals have a protected status, but they have been repeatedly targeted during the Gaza war.

Israel accuses Hamas, which continues to retain its weapons and maintain security control over the Gaza Strip, of using hospitals for military purposes. It says the group stores weapons and runs command and control rooms in hospitals, which Hamas denies.

Earlier, civil defence spokesperson Mahmoud Basal told news agency AFP that six people had been killed. The BBC is prevented by Israel from reporting independently from inside the Gaza Strip, and is unable to verify details of the incident.

Recovery work is carried out by the Civil Defence in Gaza, which operates under the Hamas-run interior ministry. Its efforts have been supported by the International Committee of the Red Cross (ICRC).

Videos shared by activists showed thick smoke inside the building and extensive destruction on the second floor, where medical equipment and beds had been scattered by the blast.

Local activists have also circulated claims that the strike may have targeted a senior Hamas security figure who was hiding inside the building.

Speaking to reporters in the aftermath of the strike, the director of Nasser Medical Complex said the building had been hit in a vertical strike, causing extensive damage to the intensive care and surgical departments for both men and women.

Nasser Hospital, the largest in southern Gaza, was hit by a double Israeli strike in August 2025, which killed at least 20 people, including journalists and health workers.

Israeli strikes on Gaza have continued despite a ceasefire agreement in October last year. More than 1,600 people have been killed since then, according to Gaza’s Hamas-run health ministry, whose figures are considered reliable by the UN.

Israel and Hamas have accused each other of violating the ceasefire.

The humanitarian crisis in Gaza has also worsened from recent heavy rains that reportedly flooded tens of thousands of tents that were housing displaced families.

The Gaza war was triggered by the Hamas-led attack on southern Israel on 7 October 2023, when about 1,200 people were killed and 251 others were taken hostage.

Since then, more than 74,645 people have been killed in Gaza, the health ministry says.