A Syrian war monitor reported an air attack Wednesday on Iran-affiliated forces in eastern Syria followed by large columns of militia trucks coming to the area.

The Syrian Observatory for Human Rights (SOHR) based in London quoted its sources in Syria that unknown aircraft, possibly drones, attacked warehouses in al-Bukamal belonging to Iran-commanded militia forces in the early hours of Wednesday. The report said that the attack might have come from Israel, or the International Coalition headed by the United States.

SOHR said the “attacks destroyed the arms and ammunition warehouses and caused huge explosions”, but no casualties have been reported.

The Syrian government, which usually is quick to announce suspected Israeli attacks on Iran-affiliated targets, has not issued a statement.

SOHR further says that convoys of trucks came to the area on November 7 and also hours after Wednesday’s attack. Al-Bukamal ciry is near Syria’s border with Iraq from where shipments and fighters sent by Iran cross the border from Iraq. The area is known as a major military staging point for Iran.

In recent weeks Israel has continued attacks on Iranian targets in Syria, without any acknowledgement.