Heavy airstrikes struck the Scientific Studies and Research Center, a Syrian government defense laboratory, as well as a military base and warehouse that housed Iranian troops and proxies in Syria. The airstrikes took place at the beginning of this week, according to Syrian state-run media SANA.  

Syrian military sources initially told the media that their air defenses thwarted the attack: “Syrian air defenses intercept an Israeli aggression on a research center in Aleppo province,” SANA reported. But then added that they were assessing the damage caused by the raids.

However, the U.K.-based Syrian Observatory for Human Rights (SOHR), which has been monitoring the civil war, said that the weapons warehouses adjacent to the Syrian defense laboratory were rocked by “violent secondary explosions” in the area. There have been no reports of casualties thus far.

The Scientific Studies and Research Center laboratory is believed to be a facility for the development of chemical weapons for Syria the development of which is aided by Iranian researchers.

The Syrians and their Russian allies have denied that they have used chemical weapons but instead blame anti-regime rebels for chemical weapons attacks.  

With Russia’s assistance, the regime of Assad has turned the tide in the civil war and has regained nearly all of the territory that it had lost.

The SOHR added that further strikes were reported near the town of el-Mayadeen in the Deir ez-Zor region. While no one has claimed responsibility for the attack in Deir ez-Zor, the SOHR said that the most “likely” perpetrator is Israel.

In the past two weeks, there have been seven airstrikes attributed to Israel on Iranian forces in Syria.