Violence flared up at the Israeli-Lebanese border on Wednesday after a Hezbollah missile attack killed two soldiers, the Associated Press reported. The Lebanese militants apparently launched the devices in retaliation for a deadly airstrike attributed to Israel, which had claimed the lives of six of their fighters in the occupied Golan Heights earlier this month.

It was the deadliest attack since a 2006 war between Jerusalem and Hezbollah, and Israeli Prime Minister Benjamin Netanyahu said his country would respond "forcefully." The Jewish state's military launched aerial and ground assault on Hezbollah positions that accidentally killed a Spanish peacekeeper, according to Lebanese officials.

"Those behind the attack today will pay the full price," Netanyahu warned, according to Reuters.

The Hezbollah branch that carried out the attack referred to itself as the "righteous martyrs of Quneitra," suggesting a connection to the Israeli strike on the Golan Heights, in which an Iranian general died on Jan. 18, in addition to the Lebanese militants.

A spokesman for the United Nations' Interim Force in Lebanon urged "maximum restraint to prevent an escalation," the BBC noted. She acknowledged that one of its peacekeepers had been killed when at least 50 artillery shells were fired at the villages of Abbasiyeh, Ghajar, Kfar Chouba and Majidiyeh.

"We are looking into the circumstances of this tragic incident," spokesman Andrea Tenenti said, though she did not specify the source of the fire.

On the Israeli side, seven soldiers were wounded, in addition to the two fatalities, according to the Washington Post.

The triangle where Israel, Lebanon and Syria meet has, after years of relative peace, seen an increasing spillover from the Syrian civil war between the terror group ISIS, moderate rebels and forces loyal to dictator Bashar al-Assad, the newspaper detailed. The embattled leader backs Hezbollah, a Shiite group, as does the Iranian regime.

In an operation unrelated to the Hezbollah strike, Israeli jets on Wednesday attacked Syrian army artillery positions near the Golan Heights in response to two rockets fired from Syrian territory the previous day, the Washington Post noted. No casualties were reported in that incident.