An activist holds a tablet with a picture of the lifeless body of a Russian pilot of a war plane shot down by Turkey, in front of the Turkish embassy in Moscow, Russia, on Tuesday.

One Russian pilot of a warplane downed by Turkey over Syria on Tuesday was killed by rebels and the second is missing after they both parachuted, rebel and opposition sources said.

A Russian helicopter was also blown up by rebels following an emergency landing in government-held territory after it was damaged by rebel fire, but its crew was able to escape, a monitor said.

The sources told AFP that the first pilot of the downed warplane was killed by opposition forces who shot at him as he landed after ejecting.

Several videos circulating online and shared on opposition social media sites purported to show the dead pilot surrounded by rebels from different factions.

Fadi Ahmed, a spokesman for the First Coastal Front rebel group, said “the Russian pilot was killed by gunfire as he fell with his parachute” in the Jabal Turkman area of Latakia province on the coast.

“The 10th Brigade (rebel group) transferred the body of the dead Russian to the local rebel joint operations room,” added Omar Jablawi, a media activist working with rebels in the area.

He declined to specify exactly where the joint operations room was located.

The sources said rebels were still searching for the second Russian pilot of the Su-24 aircraft, which Ankara said was downed by Turkish forces after violating its territory.

The Syrian Observatory for Human Rights said Russian helicopters were combing the area between Jabal Turkman and government-held Kassab on the Turkish border searching for the second Russian.

Nearby, the monitor said rebels fired on a Russian helicopter, damaging it and forcing it to make an emergency landing in government-held territory.

The crew was able to flee but rebels blew up the helicopter shortly afterwards with a TOW anti-tank missile, the monitor said.

A video circulating online purported to show the helicopter on the ground being blown up.

US-made TOW missiles have been supplied by Washington and other rebel backers to several opposition groups in Syria.

Also online, opposition and rebel accounts on Twitter and Facebook circulated several videos depicting from several angles the man said to be the dead Russian pilot.

In them, a man can been seen in military uniform with straps across his chest and blood on his face.

Rebels refer to the man as a “Russian pilot” and “Russian pig,” but the location of the footage was not specified and it was impossible to verify the videos.

Russia began an air campaign in Syria on September 30, saying it was targeting the Daesh jihadist group and other “terrorists.”

But Syria’s rebel groups and their backers accuse Moscow of focusing on Islamist and moderate opposition fighters rather than jihadists.

Fierce battles have raged for the past several days between rebel groups, not including IS, and regime forces backed by Russian air power in parts of northern Latakia province.

The regime has made some advances, though the frontline has shifted in both directions, according to the Observatory.

Related articles across the web

• 75 US-trained rebels enter Syria from Turkey: monitor
• New Group of U.S.-Trained Rebels Enter Syria
• SYRIA: ' Seventy Five US-Trained-Syrian rebels enter fight against Islamic State - monitor '
• 75 US-trained militants enter Syria via Turkey: Report
• Second Batch Of Obama's US-Trained "Moderate" Syrian Fighters Cross Into Syria To Battle ISIS, Promptly Arrested By Islamist Rebels...
• Syria deploys Russian drones for first time
• 75 U.S.-trained rebels enter Syria to fight IS: monitor
• Activists report 75 US-trained rebels return to Syria
• Chechen, Tajik, Uzbek Group Vows Loyalty To Al-Qaeda's Syrian Wing
• Ceasefire in 3 Syria battlegrounds between government forces and militants begins