Israeli Air Force (IAF) aircraft hit at least 18 sites that house Iranian troops and weapons storage facilities near the Iraqi border in Syria on Tuesday night. This is a sign that Israel is ratcheting up pressure on Iran and its proxy militias in the country, despite the upcoming change of administrations in Washington.

Casualties are listed as 23 killed and 28 wounded. Yet, the death toll is expected to rise as many troops and militiamen were seriously injured in the airstrikes.

This is the third and largest airstrike against an Iranian-linked presence in Syria in the past month. Initial reports had the airstrikes hitting as many as 50 different targets. The strikes come on the heels of an extensive Israeli leaflet drop campaign aimed at reducing civilian deaths.

Due to the problems of conducting airstrikes so far from Israeli air space this particular operation targeted Iranian positions close to the Iraqi border. This may account for the large number of targets engaged in the operation, which makes it a rarity among Israeli airstrikes.

Syrian official state news agency SANA reported that the airstrikes targeted sites in the Boukamal and Deir Ezzor areas in eastern Syria. These areas host a large concentration of Iranian Quds Force members and Iranian-backed militias, including Hezbollah.

“At 1:10 a.m., the Israeli enemy carried out an aerial assault on the town of Deir Ezzor and the Al Bukamal region,” SANA said, quoting a military source.

“The results of the aggression are currently being verified,” the report added.

The Syrian Observatory for Human Rights (SOHR), a U.K. watchdog for the Syrian civil war, said that Israeli airstrikes targeted 10 warehouses, bases, and other positions on the outskirts of Deir Ezzor city. Additionally, six bases, weapons warehouses, and ammunition depots were targeted in the Al-Bokamal desert; two targets in the Al-Mayadeen desert were also hit. Several of the targets were hit more than once.