A military airport in Syria has been targeted in a foreign missile strike, killing at least 14 people and injuring a number of others, a war monitor says. The attack is believed to have been carried out by Israeli warplanes.

The assault began at about 3:30 a.m. local time on Monday when residents in parts of Lebanon reported hearing loud booms and the sound of jets flying overhead. One video which was shared online showed a bright light moving across the sky towards Syria.

Syria’s state-run news agency reported that the Tiyas Military Airbase in Homs province had been hit by missiles, killing and injuring an unknown number of people. It claimed that Syrian air defenses responded to the attack and shot down eight of the missiles.

Tiyas Military Airbase, which is also known as T4, is one of Syria’s largest airbases and is located about 85 kilometers (53 miles) southeast of Homs, or 165 kilometers (102 miles) northeast of Damascus. The airbase is also used by special forces of Iran’s Revolutionary Guards.

The Syrian Observatory for Human Rights, which is based in Britain and uses a network of sources to track casualties across Syria, reported that at least 14 people were believed to have died in the attack. Iranian forces are among those killed, the observatory said.

U.S. President Donald Trump had warned of a “big price to pay” after the chemical attack, calling Syrian President Bashar al-Assad an “animal,” but officials in Washington, D.C. were quick to rule out any U.S. involvement in the missile strike.

France, which has called the use of chemical weapons a “red line,” also denied any involvement.

Russia’s defense ministry said the attack was executed by Israel, which carried out airstrikes in Syria just a month ago, including one against a UAV control car at Tiyas Military Airbase. The Israeli government has refused to comment on the reports.

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