The capture by Iraqi and Syrian forces of the Islamic State group's last bastions failed to clarify the fate of several foreign hostages thought to have been kidnapped by jihadists.

 The Syrian city of Raqa, which US-backed forces retook in mid-October, was the group's inner sanctum and where many of the kidnapped foreigners were sequestered.

Following is what we know about John Cantlie, a British journalist who was kidnapped by IS five years ago on Wednesday, and about other foreigners still believed held or missing in Syria:

JOHN CANTLIE

British journalist John Cantlie was detained by the Islamic State group on November 22, 2012.

He was kidnapped along with US reporter James Foley, who became the first of a string of foreign hostages to be slain in gruesome propaganda videos.

Cantlie however appeared in several subsequent videos released by IS in which he delivered jihadist propaganda to the camera in the style of a news report.

His last appearance was during the battle for Mosul late last year. He looked very gaunt and tired.

His current whereabouts are unknown and Cantlie's family have chosen discretion as a way of increasing his chances of survival.

GRIGORY TSURKANU AND ROMAN ZABOLOTNY

The pair, believed to be Russians, were captured in September or early October iDeir Ezzor province in eastern Syria.

Moscow never confirmed the identity of the two men, who appeared in an IS propaganda video. A Cossack group identified them as two veterans from southern Russia in their late thirties.

Some Russian media reports said they were mercenaries for a shadowy outfit called Wagner which has been sending ex-servicemen to fight alongside Syrian regime forces.

A Russian newspaper said they were executed but their deaths were never confirmed.

SKY NEWS TEAM

Mauritanian national Ishak Moctar and Lebanese national Samir Kassab went missing on October 15, 2013, along with their Syrian driver, near the northern city of Aleppo.

They were believed held by IS but their fate was never confirmed and they are still considered missing. The pair were believed to still be alive in 2016 and held in Raqa.

JUMPEI YASUDA

Japanese journalist Jumpei Yasuda is thought to have been abducted by the Al-Nusra Front jihadist group, a former Al-Qaeda affiliate, in northern Syria in 2015.

Tokyo describes him as missing. A picture of him holding a piece of paper that read "Help me, this is the last chance" was released in mid-2016 and deemed authentic.

AUSTIN TICE

The 36-year-old American journalist was kidnapped in Syria in August 2012 by unidentified armed men after reporting south of Damascus.

His kidnapping was never claimed by any organisation but his family says it has reason to believe the Texan reporter is still alive.

PAOLO DALL'OGLIO

The Jesuit priest known to most as Father Paolo was a well-known figure in Syria, where he lived for years in the 6th century Deir Mar Musa monastery that he renovated, north of Damascus.

He was exiled from Syria in 2012 for meeting with members of the opposition to President Bashar al-Assad's regime and kidnapped by the Islamic State group near Raqa when he returned the following year.

He was reported to have been executed and his body dumped in a crevice soon after but his death was never confirmed by any party.

source: AFP