Search and rescue operations are ongoing after an Israel Defense Forces strike on a school in Gaza killed at least 17 people and wounded over 18 others, according to Gaza Civil Defense.

This is the fifth time the IDF has bombed this school. It was previously struck by the IDF on July 6.

Six of the people killed in the strike worked for the United Nations Relief and Works Agency for Palestine Refugees in the Near East, according to the agency. Among those killed was the manager of the UNRWA shelter and other team members providing assistance to displaced people.

About 12,000 displaced people live in the school, mainly women an children, according to the UNRWA.

The IDF, confirming the strike, claimed that the school had been used by Hamas terrorists to plan and execute attacks against Israel.

An Israeli air force helicopter crashed in the Rafah area of the Gaza Strip, killing two soldiers overnight Tuesday into Wednesday, the Israel Defense Forces said.

The helicopter was "on a mission to evacuate an injured solider to a hospital for medical treatment," the IDF said. An initial inquiry "indicates the crash was not caused by enemy fire," but the cause of the crash is still "under investigation," the IDF said.

Seven additional soldiers were injured "to varying degrees" and were evacuated to a hospital for treatment, the IDF said.

The families of the killed and injured soldiers have been notified, the IDF said.

-ABC News' Jordana Miller

Egyptian and Qatari officials met with a top Hamas official in Doha on Wednesday, hoping to potentially restart cease-fire negotiations after they fell apart again.

Hamas is repeating its demand that the deal proposed in early July be put back on the table, according to a statement confirming the meeting. Hamas also reiterated its demand for a total withdrawal of Israeli forces from the Gaza Strip.

As of Tuesday evening, 82.5% of children in the Gaza Strip under the age of 10 have received their first dose of the polio vaccine as part of the ongoing emergency polio vaccination campaign.

The third round of vaccinations continues "despite the ongoing occupation aggression on the Strip, despite the great danger to their movement and travel between vaccination centers, and this is the case of our people in the Strip who are keen to vaccinate children against the disease," the Palestinian Ministry of Health said in a statement Wednesday.