The State Department is "urgently working to get more information" on the killing of American citizen Aysenur Ezgi Eygi in the West Bank last week, Principal Deputy Spokesperson Vedant Patel told journalists at a Monday briefing.

Eygi, 26, was an activist working for the International Solidarity Movement and was shot dead in the West Bank village of Beita on Friday. The dual American-Turkish citizen was allegedly killed by Israeli troops.

Patel told reporters that "our partners in Israel are looking into the circumstances of what happened, and we expect them to make their findings public, and expect that whatever those findings are, expect them to be thorough and transparent."

-ABC News' Jordana Miller and David Brennan

The Israel Defense Forces (IDF) said a Monday night strike on tents in a designated humanitarian zone in the southern Gaza Strip targeted Hamas figures "directly involved" in the Oct. 7 attack.

The Hamas-run Gaza Civil Defense reported at least 40 people killed and at least 60 injured in the bombing. Search and recovery efforts were underway at the scene on Tuesday.

The IDF said Tuesday that its strike targeted "senior Hamas terrorists" in a "command and control center embedded inside the humanitarian area in Khan Younis."

Among those killed were Samer Ismail Khadr Abu Daqqa, the head of Hamas' aerial unit in Gaza, the IDF said.

Osama Tabesh, the head of the observation and targets department in Hamas' military intelligence headquarters, and Ayman Mabhouh, another "senior Hamas terrorist" were also hit, the force said.

"According to an initial review, the numbers published by the Hamas-run Government Information Office in Gaza, which has consistently broadcast lies and false information throughout the war, do not align with the information held by the IDF, the precise munitions used, and the accuracy of the strike," the IDF statement added.

-ABC News' Jordana Miller and David Brennan

At least 40 people were killed and at least 60 people have been wounded after an Israeli strike in a designated humanitarian area of Khan Yunis, according to the Hamas-run Gaza Civil Defense.

The strike hit "a gathering of displaced persons' tents consisting of at least 20 inhabited tents," a Gaza Civil Defense spokesperson said early Tuesday morning local time.

The Israeli Air Force "struck significant Hamas terrorists who were operating with a command and control center embedded inside the Humanitarian Area in Khan Yunis," the Israel Defense Forces said in a statement.

-ABC News' Sami Zyara, Diaa Ostaz and Dana Savir

The White House is remaining hopeful that talks for a cease-fire in Gaza and release of the remaining hostages can be salvaged after Hamas proposed new amendments to the deal following the killing of six hostages.

"Hamas did change some of the terms of the exchange. And that has made it more difficult for us to get there," National Security Communications Adviser John Kirby said at Monday’s press briefing.

"We still believe that, even for the new amendments that Hamas has made, that it's still worth an effort to try to see if we can't get back into a cease-fire negotiation," he added. "But we're not there right now."

Kirby would not say if President Joe Biden will be increasing pressure on Israeli Prime Minister Benjamin Netanyahu to accept a deal and potentially hold the transfer of weapons to Israel in order to secure a deal, similar to the recent decision by the United Kingdom.

"I can't think of anything we haven't put more pressure on ourselves than to try to get this deal," Kirby said. "We know how urgent this is. And we're working night and day to try to see if we can get a deal in place. Hamas is the main obstacle to this right now."

-ABC News' Justin Ryan Gomez