Israel has protested to the United Nations Security Council after a terror tunnel was discovered under two UN-run schools in the Gaza Strip, appealing to the world body to condemn Hamas and prevent its facilities being exploited by the terror group, the Foreign Ministry said Saturday.

Israel’s Ambassador to the United Nations Danny Danon submitted the letter of protest to UN Secretary-General Antonio Guterres and the UN Security Council.

“The latest finding verifies once again that Hamas’s cruelty knows no limits, including endangering centers of learning and education, and using children as human shields,” Danon wrote.

The tunnel was discovered by workers of the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA) on June 1 under two schools in the Maghazi refugee camp in the Gaza Strip near the city of Deir al-Balah.

“I call on the Security Council to strongly and unequivocally condemn Hamas and its repeated abuse of civilian infrastructure, and designate this group as a terrorist organization,” Danon continued.

“It is of the utmost importance that the Council ensures that all UN-affiliated agencies, and especially UNRWA, remain neutral and safeguarded from abuse by terrorist organizations.”

The tunnel, between two and three meters underground, passes under the Maghazi Elementary Boys A&B School and the Maghazi Preparatory Boys School, and was built both westward into the Palestinian enclave and eastward toward the security fence with Israel, according to UNRWA.

UNRWA spokesman Christopher Gunness said Friday that the tunnel “has no entry or exit points on the premises nor is it connected to the schools or other buildings in any way.”

Illustrative: An image taken from a video on Hamas's Facebook page on July 20, 2016 shows Palestinian children entering into a tunnel dug by the terror group in the Gaza Strip. (Screen capture from Facebook)

Illustrative: An image taken from a video on Hamas’s Facebook page on July 20, 2016 shows Palestinian children entering into a tunnel dug by the terror group in the Gaza Strip. (Screen capture from Facebook)

“UNRWA condemns the existence of such tunnels in the strongest possible terms. It is unacceptable that students and staff are placed at risk in such a way,” he said.

Gunness said the agency had “robustly intervened and protested to Hamas in Gaza”.

He said UNRWA will seal the tunnel, which was discovered while the schools were empty during the summer holiday.

Hamas, for its part, denied that it or any other terror group built a tunnel under the two UN schools. The organization on Friday “strongly condemned” the UNRWA revelation, saying it would be exploited by Israel to “justify its crimes.”

The terror group denied it built the tunnel and said it had clarified the issue “with all factions and resistance forces, who clearly stated they had no actions related to the resistance in the said location,” the movement said, adding that it respected UNRWA’s work.

US Ambassador to the UN Nikki Haley visits at a terror tunnel built by Hamas on the border of Israel with the Gaza Strip, June 8, 2017. (Matty Stern/U.S. Embassy Tel Aviv)

US Ambassador to the UN Nikki Haley visits at a terror tunnel built by Hamas on the border of Israel with the Gaza Strip, June 8, 2017. (Matty Stern/US Embassy Tel Aviv)

Over the years, Gaza’s Hamas rulers have built a labyrinth of tunnels, some passing under the border into Israel which they used to launch attacks during their last conflict in 2014. Hamas also built a vast network of tunnels under Gaza’s border with Egypt to smuggle goods and weapons.

The Israeli army found and destroyed several tunnels during the 2014 war.

UNRWA has long been criticized by Israel for aspects of its handling of relations with Hamas, and Israel has claimed that some of UNRWA’s Palestinian employees support terrorist activities and spread anti-Semitism online.

In February, a UN watchdog group released a report showing screenshots from the Facebook pages of 40 UNRWA school employees in Gaza and other parts of the Mideast that it said “incite to Jihadist terrorism and anti-Semitism, including by posting Holocaust-denying videos and pictures celebrating Hitler.”

In April, the agency said a Gaza staffer suspected of having been elected to Hamas’s leadership no longer works for it but declined to clarify whether he was fired or resigned after Israel voiced its objections.

An independent UN inquiry found in 2015 that Palestinian armed groups hid weapons in three empty UN-run schools in Gaza and that in at least two cases terrorists “probably” fired rockets at Israel from the facilities during the summer war in 2014 between Israel and the Gaza Strip.