An Israeli drone strike on a car crossing through a Syrian checkpoint near the border with Lebanon on Wednesday killed three Palestinian fighters and one member of Lebanese armed group Hezbollah, two security sources told Reuters.

The Israeli military said the strike killed Faris Qasim, who it said was significant figure in the operations division of the Iranian-backed militant group Islamic Jihad, responsible for operational plans in Syria and Lebanon.

It said he had a central role in recruiting Palestinians to Hezbollah to attack Israel from Lebanon. Other Islamic Jihad militants who were on their way from Syria to Lebanon were also killed in the strike, it said, without providing details.

The security sources said the car was not transporting weapons. There was no immediate comment from Hezbollah or from the Palestinian Islamic Jihad movement, to which one of the sources said the three Palestinian fighters belonged.

Local Syrian official Abdo al-Taqi told a Syrian radio station that a car was targeted on Wednesday morning on the road between the Syrian capital Damascus and Lebanon’s capital Beirut, and four people were killed.

Hezbollah, Islamic Jihad and other armed factions have launched rockets and drones at Israel from southern Lebanon. The groups have strong ties to Iran and to Syria’s government and have transported fighters and weapons through the porous Syrian-Lebanese border.

Israel has targeted weapons shipments and other military infrastructure in Syria for years and has stepped up its strikes there since October, when the Gaza war began.

Wednesday’s drone strike came hours after an Israeli airstrike hit a pickup truck in northeast Lebanon near the Syrian border. A security source told Reuters that the vehicle was carrying military equipment, likely a damaged rocket launcher on the way to be repaired.