Photo: AP

A series of seven nearly simultaneous suicide bombings ripped through two regime-held cities in Syria on Monday, Agence France-Presse reports, leaving more than 120 people dead and many more wounded. The Islamic State claimed responsibility.

According to the Syrian Observatory for Human Rights, 73 people were killed in the city of Jableh and another 48 in Tartus. The head of the monitoring group, Rami Abdel Rahman, said these were “without a doubt the deadliest attacks” on the cities—strongholds for President Bashar al-Assad’s regime—since the civil war began in 2011.

Tartus was hit by one car bomb and two suicide bombers; one of those attacks was on a bus station. AFP reports:

A Facebook page sharing local news from Jableh, where another bus station was targeted, as was a government hospital, shared footage of people around fire trucks near several bombed-out cars.

A police officer in Jableh told AFP that one suicide attacker detonated his explosives inside the emergency room of the state-run hospital, while three car bombs caused the other blasts.

The Observatory said there were three suicide attackers and just one car bomb.

Russia, long an ally to Assad, maintains a naval base in Tartus. (ISIS do not usually strike Syria’s coastal provinces; al-Nusra Front, the local al-Qaeda affiliate, is much more influential in the area.).

“The rising tensions and terrorist activity in Syria can only spark great worry,” Putin spokesman Dmitri Peskov said at a press conference. The attacks “demonstrate yet again how fragile the situation is in Syria and the need to take energetic measures to relaunch peace talks.”

In response to a question about whether Russia would begin increasing its presence again, Peskov said the country’s bases in Syria permit “a very flexible approach” to the number of troops deployed. Last week, Russian military officials called for joint airstrikes with the United States against al-Nusra Front.