Israel, according to foreign reports, has assisted Egypt throughout its fight against the Islamic State insurgency in the northern Sinai Peninsula, including intelligence sharing and even allegedly carrying out drone strikes against the terrorists.

But in the wake of the deadliest terror attack ever on Egyptian soil, Israeli officials were evasive on specific actions being taken by Israel following the devastating mosque massacre on Friday that killed over 300 people, including at least 27 children.

“The Israeli defense establishment expressed its sympathies and, as always, is willing to lend a hand to any country in order to help fight terror,” an Israeli security official said Sunday, speaking on condition of anonymity.

“That’s how it was in this case, and how it will also be in the future,” he added.

Asked specifically if Israel was cooperating with the Egyptians, Finance Minister Moshe Kahlon told Channel 13 in an interview that “this is an issue to discuss in the cabinet.”

Israel has assisted Egypt throughout its fight with the Islamic State terrorist group in the Sinai, and its precursors. According to foreign reports, this has included conducting drone strikes in the peninsula on Islamic State targets. It has also reportedly taken the form of significant intelligence sharing.

More publicly, since 2013, Israel has also allowed additional Egyptian forces into the peninsula, beyond the level permitted under the 1979 peace accord between the two countries. Heavy weapons, like tanks, artillery and attack helicopters, have been brought into Sinai to fight the Islamists, a sign that Jerusalem is not concerned those big Egyptian guns could be turned against it.

According to Egyptian media on Sunday, the country has yet to ask Israel to permit it to bring in even more troops to the restive region. An Egyptian military spokesperson did not immediately respond to requests for confirmation.

IS, which is conducting a deadly insurgency in the Sinai, has not claimed responsibility for the attack, but it is the main suspect as the terror group has branded Sufi Muslims “heretics.”On Friday, a group of 25 to 30 armed terrorists, wearing camouflage and carrying Islamic State black flags, carried out the deadly massacre at a mosque that is associated with followers of the mystical Sufi branch of Sunni Islam outside the northern Sinai city of al-Arish, Egyptian officials said Saturday, as the death toll rose to 305, including 27 children.

A statement by Egypt’s chief prosecutor, Nabil Sadeq, said Friday’s attack left another 128 people wounded.

It said the terrorists arrived at the mosque close to the small town of Bir al-Abd in five all-terrain vehicles and positioned themselves at the main door and the facility’s 12 windows. After setting off an explosion in the mosque, they opened fire on the fleeing worshipers.

“This is a serious threat and challenge presented by people of darkness, who indiscriminately slaughter kids, families, adults and the elderly,” the Israeli defense official said Sunday.

The Prime Minister’s Office on Saturday condemned the “terrible and despicable terror attack carried out on the Mosque near al-Arish and send condolences in the name of all the citizens of Israel to President (Abdel-Fattah) el-Sissi, the Egyptian nation, and the families of the victims.”

In the statement, the prime minister added, “The terror will be defeated faster if all nations work together against it.”

Also Saturday, President Reuven Rivlin condemned the attack as “pure evil.”

In response to the gruesome attack, the Egyptian military launched a reprisal campaign, sending air force jets to destroy the vehicles used in the mosque attack and target locations where weaponry was stored, Egyptian army spokesperson Tamer el-Refai said on Friday.

Israel has had relatively few direct run-ins with the Islamic State group affiliate in the Sinai Peninsula, though it had more clashes with the group’s predecessor, Ansar Bait al-Maqdis.

The jihadists there have launched rockets at Israel on multiple occasions, most recently in October. The most daring took place in February when multiple missiles were fired at the southern city of Eilat, far from the terror group’s home base in the northern Sinai

Analysts say these rocket attacks against Israel are more likely a propaganda exercise than serious attempts to start a war with the Jewish state.

In July, Bloomberg news reported that Israel has carried out multiple drone strikes against the Islamic State affiliate in the Sinai, citing an unnamed former senior official.

The airstrikes were conducted with Egypt’s knowledge and blessing, according to the ex-official, who spoke to the US-based news site on condition of anonymity.

According to foreign reports, Jerusalem and Cairo have long cooperated closely on security measures in the Sinai and Gaza. However, the report shed additional light on the countries’ covert security cooperation, which has come along with increasingly close ties on the political front.

Islamists in the Sinai, who have pledged allegiance to the Islamic State in 2014, have waged an insurgency against Egyptian forces since the ouster of president Hosni Mubarak in 2011.

Fighting has intensified in recent years, following a 2013 coup by current President Abdel-Fattah el-Sissi to remove Muslim Brotherhood-linked leader Mohammed Morsi from power.

The two countries have entered something of a golden age in their relationship since Sissi assumed the country’s leadership.

“This is one of the best times we’ve ever had,” in terms of cooperation between governments, Israeli ambassador to Cairo Haim Koren said last year. “There’s good cooperation between the armies, we have understandings about the Sinai Peninsula, and basically, we see (eye-to-eye) on development of the region.”

After decades of wars followed by years of an uneasy peace, Israel has emerged as an increasingly public ally to Sissi, along with powerhouse Saudi Arabia and smaller, wealthy Gulf Arab countries.

Israel often praises Sissi for his tough stance on terrorism, and considers him a key ally in what it sees as a shared battled against Islamic extremists.

Agencies contributed to this report.