Israel’s military said it has begun ground operations against Hamas in Gaza, escalating its offensive against the militant group.

Lt. Col. Jonathan Conricus, an Israeli military spokesman, said ground and air forces are striking targets in Gaza from the Israeli side of the border, including tanks and artillery. He initially said Israeli troops had entered the Gaza Strip but later retracted that statement.

“There are ground forces currently deployed along the border area and they are engaging and attacking the Gaza Strip from there,” said Col. Conricus.

Israel’s military didn’t give more details about the operation, but some 3,000 to 4,000 troops have been amassed on the border in recent days, military officials have said. Those figures suggest a more limited operation because a full-scale invasion would require many more troops.

It isn’t immediately clear how big the ground operation is or what its aims are, but if troops actually cross into Gaza it would be the first time since the 2014 war that Israeli troops have entered Gaza to fight.

“I said we’d exact a steep price from Hamas, and that’s what we’re doing…The last word has not been said and this operation will continue for as long as it’s necessary,” Prime Minister Benjamin Netanyahu said on Twitter early Friday.

The military’s move follows days of fighting. Since Monday, Israel has struck more than 600 targets that it described as Hamas and Palestinian Islamic Jihad weaponry and infrastructure, and killed more than 30 militants, Col. Conricus said.

The strikes have killed more than 103 people in Gaza, including 27 children, according to Palestinian officials. Seven Israeli civilians, including one child, have been killed in the rocket fire from Gaza, while one soldier was killed by an antitank missile, according to Israeli authorities.

A spokesman for Hamas’s military wing played down the implications of Israel’s expanded efforts.

“The enemy carries out show raids aimed at sabotage and destruction,” he said. “It will not affect the capabilities of the resistance.”

Hamas and Palestinian Islamic Jihad have fired at least 1,750 rockets toward Israel since Monday evening, including 300 that have fallen short and landed in Gaza, he said, adding that Israel’s Iron Dome missile-defense system has had a 90% interception rate.

Israel and Hamas have fought three wars since the militant group seized control of the Gaza Strip in 2007. They also have seen several escalations since spring 2018 that have almost developed into full-blown conflict.

Israel’s latest move came as the Israeli government scrambled to contain escalating violence within its own borders.