Scores dead in IS attacks on Syrian government's coastal stronghold

At least 148 people were killed and many more wounded in seven near-simultaneous explosions in the Syrian government strongholds of Tartus and Jableh on Monday, according to the monitor Syrian Observatory for Human Rights.

The monitor's head, Rami Abdel Rahman, called the blasts "unprecedented" in cities like Tartus and Jableh, which have not seen large attacks since the 1980s.

"I'm shocked, this is the first time I've heard sounds like this," said Mohsen Zayyoud, a 22-year-old university student in Jableh.

There were also reports of a retaliatory arson attack on a camp for internally displaced people in Tartus, in the aftermath of the string of bombings.

On Monday morning, in the small coastal town of Jableh, some 30km south of Latakia, 100 people died in four explosions, three of them suicide blasts.

Two of the blasts in Jableh reportedly hit the emergency department of a local hospital.

One of the bombers arrived at the hospital and appeared to be helping people who were injured in an explosion that hit minutes earlier, before blowing himself up just inside the entrance, local news site Tartous Today reported.

The hospital's emergency department was completely destroyed by the bomb, the site reported.

Another attack hit the city's electric power plant, killing ten people.

Footage circulated on social media appeared to show members of the security forces detaining a man suspected to be a failed suicide bomber after the string of attacks in Jableh.

In the city of Tartus further south, 48 people were killed in three blasts - at least two of them suicide attacks - that hit a bus station, monitoring group the Syrian Observatory for Human Rights said.

Local hospitals in Tartus - which is also the site of a Russian naval base - put out an urgent call for blood donations after the blasts, warning that many of those injured are in critical condition.

There were also reports that a fire at al-Kernak camp in the small town of Amrit, just outside Tartus, was started deliberately in retaliation for the deadly bombings.

The camp mainly houses internally displaced people who belong to the country's Sunni Muslim majority.

Pro-government sites also reported that a resident of Tartus killed seven people at a camp inside the city for internally displaced people after learning that his brother had been killed in one of the blasts. However, these reports could not be verified.

The news site Tartous Today put out an editorial statement following the reports, saying that "IDPs are your brothers, and an injury to you is an injury to them.

"If they were sectarian they would not have fled here [to a Shia-dominated area], and if you were sectarian you would not have hosted them."

The governor of Tartus also called for calm and announced that the men who attacked the area on Monday had not been living nearby, a reference to a rumour suggesting that one of the bombers was originally from Idlib, but had been living in an IDP camp near Tartus.

The Islamic State (IS) group has claimed the blasts through its media arm Amaq, saying IS militants had targeted "gatherings of Alawites," the religious sect from which President Bashar al-Assad hails.

Russian news sites had earlier reported that Ahrar al-Sham claimed to have carried out the attacks.

The Syrian government has condemned the attacks, saying in a statement that the bombings - which the statement said were launched with support from countries like Qatar, Turkey and Saudi Arabia - were a response to recent battlefield advances by the Syrian army. 

Such large-scale, coordinated attacks rarely hit cities in Latakia province, which is known as a stronghold of support for Assad and is home to a high concentration of Syria's Alawite minority.

Towns like Tartus have been largely insulated from the chaos that has devastated Syria over the past five years, although large numbers of young men from the city have been killed fighting for Assad's forces.

"It's the first time we've heard explosions in Tartus, and the first time we've seen dead people or body parts here," said Shady Osman, a 42-year-old bank employee.

US urges Russia to pressure Assad

Also on Monday, the United States urged Russia to press Syria to stop bombing opposition forces and civilians in Aleppo and the Damascus suburbs.

The appeal came in a phone call from Secretary of State John Kerry to his Russian counterpart Sergei Lavrov.

"Russia has a special responsibility in this regard to press the regime to end its offensive attacks and strikes that kill civilians, immediately allow relief supplies, as determined solely by the UN, to reach all in need, and to comply completely with the cessation of hostilities," State Department spokesman Mark Toner said.

It was not clear if the call came before or after the news of the IS bombings in Tartus and Jableh.

The United States and Russia are co-partners in the so-called Vienna diplomatic process of the International Support Group for Syria, which met last week in the Austrian capital but made no notable progress.

The 20 world and regional powers taking part in the process have so far failed to turn a fragile cessation of hostilities in Syria, in effect since 27 February, into a durable truce between the government and opposition groups.

Toner said the government of President Bashar al-Assad was using air strikes and attacks on civilians to gain tactical advantage.

He said the United States is looking to Russia to provide the pressure needed to get the regime "to reconsider the fact that if this keeps up, we may be looking at a complete breakdown of the cessation".

He said a cessation of hostilities was needed to create an environment for negotiations to begin.

Indirect negotiations between the government and the opposition have been held three times in Geneva under the auspices of the United Nations, but have made no progress. No date has been set for their resumption.

"Such a [diplomatic] solution will allow all parties to focus on the shared threat posed by Daesh and other terrorists," Toner said, using an Arabic acronym for IS.