Hundreds of inmates in a Syrian prison have been observing a hunger strike to demand their release, a detainee and a monitoring group said on Tuesday.

The prisoners being held in Homs, in central Syria, include prisoners of conscience who were jailed for taking part in anti-government protests when the conflict broke out nearly four years ago.

The Islamic State group has published what it says is an interview with a Jordanian pilot it captured after his plane crashed in Syria last week.

In the comments attributed to the pilot, he says his plane was hit by a heat-seeking missile, endorsing the jihadist group's version of events, which has been rejected by both Jordan and the United States.

The Turkish coastguard was searching Monday for eight people believed to be Syrian migrants missing after their boat capsized off southwestern Turkey while on its way to Greece, news reports said.

Rescuers have found two people alive but were still searching for eight others off the Aegean resort of Bodrum, the Dogan news agency reported.

A car bomb explosion near a gas plant in Syria's Homs province on Monday killed nine people including four soldiers, a monitoring group said, updating an earlier toll.

The jihadist Islamic State (IS) group claimed responsibility for the attack and said the two bombers were killed.

Prosecutors in Sunni-ruled Bahrain charged Shiite opposition chief Sheikh Ali Salman on Monday with promoting regime change in the Gulf kingdom through hatred and violence.

The prosecution said Salman, whose detention on Sunday triggered ongoing clashes between protesters and police, will remain in custody for further questioning on Tuesday.

The army opened fire in the air on Monday to disperse protesters near Arsal's Wadi Hmeid crossing, demonstrating against the measures in the area.

The state-run National News Agency reported that Lebanese and Syrian nationals held a sit-in near Wadi Hmeid crossing to protest the army's upped security measures along the outskirts of Arsal.

A car bombing killed six people including two children in a Kurdish area of Syria's northern province of Aleppo on Sunday, a monitoring group said.

The Syrian Observatory for Human Rights said the attack targeted a checkpoint in a town controlled manned by Kurdish forces in the Qitna area.

Islamic State group jihadists have murdered nearly 2,000 people in Syria -- half of them from an important Sunni tribe -- since announcing their "caliphate" in June, a monitoring group said Sunday.

Turkish Prime Minister Ahmet Davutoglu on Sunday warned that the government would take action against any further violence in the southeast after three people were killed in fresh clashes between two rival Kurdish groups.

"We will stand firm ... against whoever dares to erode our unity through provocative actions," Davutoglu told his ruling party supporters in the southern province of Hatay bordering Syria.

A senior Iranian military officer has been killed while advising Iraqi troops in their fight against the Islamic State group, Iran's Revolutionary Guards said on Sunday.

"Brigadier General Hamid Taghavi was martyred during a mission to advise the army and Iraqi volunteers... in the city of Samarra," north of Baghdad, said a statement from the elite Iranian military force.