Israel’s army said Friday its aircraft struck infrastructure in the Gaza Strip used by Hamas that rules the coastal territory after militants there continued for the third day to fire mortars at forces along the border.

“In response to the ongoing attacks against Israeli forces, Israel Air Force aircraft targeted a Hamas terror infrastructure,” a military statement said.

Military spokesman Lt. Col. Peter Lerner said: “The repeated attacks against the IDF activities to locate and destroy cross border tunnels will not be tolerated. Hamas’ diabolical plan to infiltrate into Israeli communities must be stopped.”

Friday’s fire comes after three days of violence in which Gaza militants fired mortars, prompting Israeli retaliation. Attacks from the enclave intensified after the Jewish state uncovered a tunnel Thursday stretching from Gaza into Israel.

Israel’s Shin Bet undercover intelligence agency said Thursday a Hamas operative arrested last month had provided useful information about the tunnel networks in the area.

The recent violence has been among some of the most serious violence between Gaza and Israel since 2014. Hamas used tunnels to attack the Jewish state during that 50-day war.

Gaza analysts have said that the flare-up of violence, the most intense since the 2014 war, threatened the truce that has largely held in the area for nearly two years.

The leader of Hamas in Gaza, Ismail Haniyeh, said the group did not want war with Israel, and that Egypt and other parties were working behind the scenes to defuse the violence.

“We are not calling for war but we will not allow incursions at all,” said Haniyeh, Hamas’ deputy chief, speaking at a mosque before Friday prayers.

“The resistance will not allow the establishment of a so-called buffer zone inside the borders of the Gaza Strip,” he stated.

Haniyeh added that mediators from Egypt, Qatar, Turkey and the United Nations had been working to restore calm along Gaza’s border and that in the meantime Israeli forces had pulled back.