Hundreds of anti-Israel protesters stormed an airport in Russia’s predominantly Muslim Dagestan region on Sunday, where a plane from Israel had just arrived, forcing security forces to close the airport and remove the demonstrators.

According to Reuters, twenty people were injured before forces contained the protest at Makhachkala airport, local authorities said. The passengers on the plane were safe, security forces told Reuters.

The unrest followed several other anti-Israel incidents in North Caucasus sparked by Israel’s war against Hamas fighters in Gaza. The Dagestani government said early on Monday that it was strengthening security measures across the republic, which is home to about 3 million people.

Videos from Makhachkala airport obtained by Reuters showed the protesters, mostly young men, waving Palestinian flags, breaking down glass doors and running through the airport shouting “Allahu Akbar” or “God is Greatest”. Another group were seen trying to topple over a patrol truck.

The Russian Aviation Authority closed the airport until it completes security checks. There were no immediate reports of arrests, but Russia’s federal investigations agency ordered a criminal probe into the incident.