Israel has conducted hundreds of strikes on Syria since the civil war began in 2011 following Assad’s crackdown on a democracy movement. Since his ouster, the Syrian Observatory for Human Rights said it had recorded more than 300 Israeli strikes.

On Monday, Israel said it had struck “remaining chemical weapons or long-range missiles and rockets in order that they will not fall in the hands of extremists”. The Observatory, which relies on a network of sources around Syria, said Israeli strikes had “destroyed the most important military sites in Syria”. The group said the strikes targeted weapons depots, boats from the Assad government’s navy, and a research centre that Western countries suspected of having links to chemical weapons production. AFP journalists on Tuesday saw the defence research centre had been destroyed. Strikes also targeted the electronic warfare administration, the Observatory said.

With Syria in flux and in the absence of a government authority just two days after Assad’s escape, AFP journalists in Damascus were unable to obtain comment from the Syrian side.

Israel, which borders Syria, also sent troops into a buffer zone east of the Israeli-annexed Golan Heights after Assad’s fall, in what Foreign Minister Gideon Saar described as a “limited and temporary step” for “security reasons”.