Deir al-Balah, Gaza Strip — An Israeli airstrike hit the fourth floor of southern Gaza’s main hospital Monday, killing at least eight people including four journalists, health officials said. An official with the civil defense rescue agency in Hamas-run Gaza said later that at least 15 people were killed in the strike in total.

Civil defense spokesman Mahmud Bassal told journalists at the scene that “the death toll is 15, including four journalists and one civil defense member,” according to the French news agency AFP.   

The victims were killed in a double-tap strike on the hospital, with one missile hitting first, then another moments later as rescue crews arrived, the health ministry said.

Khan Younis’ Nasser Hospital, the largest in southern Gaza, has withstood raids and bombardment throughout 22 months of war, with officials citing critical shortages of supplies and staff.

Asked about the strike and journalists being among the victims, the Israel Defense Forces issued a statement saying it had carried out an attack and adding that it would “conduct an initial inquiry as soon as possible,” adding that it regretted “any harm to uninvolved individuals and does not target journalists as such.”

A hospital official told CBS News that four journalists were killed in the Monday morning double-tap strike at Nasser Hospital. The official identified the four as Hossam al-Masri, who worked for the Reuters news agency, Mohammed Salama, who worked for Al Jazeera, and freelance journalists Maryam Abu Daqqa and Moaz Abu Taha.

The Associated Press’ news director for the Middle East, Jon Gambrell, said in a social media post that Abu Daqqa had “freelanced for the AP since the Gaza war began.”

Reuters confirmed that al-Masri had worked for the international news agency. It said photographer Hatem Khaled, who also worked as a contractor for the agency, was wounded. 

At least one other journalist was wounded in the strike, a hospital official said, identifying the man as Haithem Omar, who also works for Reuters.

Israel has come under mounting pressure over the number of journalists being killed in its military operations in Gaza — including in targeted strikes against individuals whom Israeli officials claim were Hamas operatives.

Israeli strikes and raids on hospitals are not uncommon. Multiple hospitals have been struck or raided across the Gaza Strip, with Israel claiming its attacks had targeted militants operating inside the medical facilities, without providing evidence.

In a statement issued Monday, the Foreign Press Association, which represents journalists working in Israel and the Palestinian territories, said it was “outraged and in shock” over the latest killings of media workers.

“This is among the deadliest Israeli attacks on journalists working for international media since the Gaza war began,” the organization said, confirming the identities of the four people killed. “These strikes hit the exterior staircase of the hospital where journalists frequently stationed themselves with their cameras. The strikes came with no warning.”

The organization demanded an immediate explanation from the IDF and from Israeli Prime Minister Benjamin Netanyahu’s office for the strike, adding: “This has gone on far too long. Too many journalists in Gaza have been killed by Israel without justification. Israel continues to block international journalists from independent access to Gaza. This must be a watershed moment. We appeal to international leaders: do everything you can to protect our colleagues. We cannot do it ourselves.”

The international Committee to Protect Journalists also condemned the Israeli strike. In a statement, the group called on the international community “to hold Israel accountable for its continued unlawful attacks on the press.”

“Israel’s broadcasted killing of journalists in #Gaza continues while the world watches and fails to act firmly on the most horrific attacks the press has ever faced in recent history,” CPJ Regional Director Sara Qudah said in the group’s post. “These murders must end now. The perpetrators must no longer be allowed to act with impunity.”

On August 11, Israel’s military targeted and killed five Al Jazeera journalists in Gaza, including correspondent Anas al-Sharif. The Israel Defense Forces said it had intelligence and documents from Gaza to prove al-Sharif was the head of a Hamas terrorist cell, and the IDF shared undated photos of Al-Sharif with Yahya Sinwar, the top Hamas leader in Gaza, who was killed last October.

CBS News could not verify the authenticity of the photos. Al Jazeera and al-Sharif had previously dismissed Israel’s claims as baseless, The Associated Press reported. Just three weeks ago, al-Sharif had appealed to the Committee to Protect Journalists over fears he might be assassinated.

A June strike on Nasser Hospital killed three people and wounded 10, according to the health ministry. At the time, Israel’s military said it had targeted Hamas militants operating from a command and control center inside the hospital.

The Hamas-run health ministry said Sunday that at least 62,686 Palestinians have been killed since Israel launched its war in Gaza in retaliation for the Hamas-led Oct. 7, 2023 terrorist attack that killed some 1,200 Israelis and saw 251 others taken as hostages.

The ministry does not distinguish in its figures between fighters and civilians, but it says around half of those killed have been women and children. The U.N. and independent experts consider it the most reliable information available on war casualties, as such figures are difficult to independently verify as Israel does not permit foreign journalists into Gaza.

Israel disputes its figures but has not provided its own.