JERUSALEM/GAZA - Israel's Defense Minister Israel Katz vowed Wednesday to dismantle Hamas if it refuses to disarm, threatening renewed military action in Gaza.

"After we complete the goal of returning all our hostages, we are determined to complete the disarmament of Hamas and the full demilitarization of Gaza," Katz said at a handover ceremony for the coordinator of government activities in the territories.

"If Hamas does not disarm under the agreed framework, we will dismantle it and all of its capabilities," Katz added.

The comments came a day after US Middle East envoy Steve Witkoff visited Israel for talks on advancing the second phase of the ceasefire, which is expected to include Gaza's reconstruction.

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Israel has said it will not allow reconstruction in Gaza without its demilitarization, while Hamas has rejected calls to disarm.

Twenty-one Palestinians killed

The Palestinian Civil Defense in Gaza said at least 21 Palestinians, including a paramedic, were killed in Israeli attacks across the Gaza Strip on Wednesday.

Mahmoud Basal, spokesperson for the Civil Defense, told Xinhua that the Israeli army had been carrying out artillery and airstrikes on Gaza City and Khan Younis in the southern Gaza Strip since dawn, targeting tents sheltering displaced people and residential buildings.

In the latest attack, an Israeli drone struck a tent housing displaced people in the al-Mawasi area west of Khan Younis, killing three, including two women and a paramedic, according to Basal.

He added that 14 people, including three children and five women, were killed and several others wounded in artillery shelling on the outskirts of the Zeitoun and Tuffah neighborhoods east of Gaza City. Some of the wounded were taken to Al-Shifa Medical Complex.

Earlier, four people, including a child, were killed in Israeli artillery shelling that targeted tents sheltering displaced people in the Qizan Rashwan area south of Khan Younis. The victims were taken to Nasser Medical Complex in the city.

Killing of Islamic Jihad commander in Gaza

An Israeli airstrike in Gaza also killed Ali Raziana, the commander of the Islamic Jihad's northern Gaza brigade, the Israeli military and the Shin Bet security agency said in a joint statement.

Raziana was killed in an airstrike conducted in retaliation for earlier gunfire in Gaza that seriously wounded an Israeli officer, according to the statement.

The statement added that Raziana was responsible for the brigade's deployment and defense plans and for coordinating attacks with Hamas against Israeli forces.

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Palestinian resistance factions agree to hold on to weapons

Meanwhile, Palestinian resistance factions have agreed to hold on to their weapons, said Mohammed Al-Hindi, a senior official of the Palestinian Islamic Jihad (PIJ).

"There is consensus among the resistance factions to hold on to the Palestinian people's weapons, and we have shown flexibility with the mediators regarding their use," Al-Hindi said in a brief statement.

The PIJ is the second-largest armed group in Gaza. Hamas has previously said that the group will give up its weapons if the Israeli occupation ends.

Gaza patients' travel through Rafah crossing

Separately, Raed al-Nams, spokesperson for the Palestinian Red Crescent Society (PRCS), said that coordination for patients traveling from Gaza through Rafah crossing has resumed.

Al-Nams made the remarks after the society said earlier in the day that Israeli authorities had canceled the departure of the third group of patients scheduled to travel through the crossing.

The office of the Coordinator of Government Activities in the Territories (COGAT), a body under Israel's Defense Ministry, said on social media on Wednesday that "contrary to reports in the Gazan media, the Rafah Crossing has opened this morning as usual, in accordance with the agreement and Israel's commitment."

The World Health Organization had notified the PRCS of the resumed coordination and the society remains committed to evacuating wounded and critically ill patients from Gaza to receive treatment abroad, Al-Nams said, noting that current efforts are insufficient to address the vast medical needs.

The spokesperson added that five patients and 10 companions were evacuated on the first day, while 16 patients and 40 companions crossed on the second day.

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The Rafah border crossing on the Palestinian side reopened on Monday for the first time in more than a year and a half, following a trial phase on Sunday, as part of the implementation of the ceasefire agreement between Israel and Hamas.