BEIRUT: A young, red-bearded ethnic Chechen has rapidly become one of the most prominent commanders in the breakaway al-Qaida group that has overrun swaths of Iraq and Syria, illustrating the international nature of the movement.

Omar al-Shishani, one of hundreds of Chechens who have been among the toughest jihadi fighters in Syria, has emerged as the face of the Islamic State of Iraq and the Levant, appearing frequently in its online videos - in contrast to the group's Iraqi leader, Abu Bakr al-Baghdadi, who remains deep in hiding and has hardly ever been photographed.

In a video released by the group over the weekend, al-Shishani is shown standing next to the group's spokesman among a group of fighters as they declare the elimination of the border between Iraq and Syria. The video was released just hours before the extremist group announced the creation of a caliphate - or Islamic state - in the areas it controls.

"Our aim is clear and everyone knows why we are fighting. Our path is toward the caliphate," the 28-year-old al-Shishani declares. "We will bring back the caliphate, and if God does not make it our fate to restore the caliphate, then we ask him to grant us martyrdom." The video is consistent with other Associated Press reporting on al-Shishani.

Al-Shishani has been the group's military commander in Syria, leading it on an offensive to take over a broad stretch of territory leading to the Iraq border. But he may have risen to become the group's overall military chief, a post that has been vacant after the Iraqi militant who once held it - known as Abu Abdul-Rahman al-Bilawi al-Anbari - was killed in the Iraqi city of Mosul in early June. The video identified al-Shishani as "the military commander" without specifying its Syria branch, suggesting he had been elevated to overall commander, though the group has not formally announced such a promotion.

As the militant group's operations in Iraq and Syria grow "more and more inter-dependent by the day, it is more than possible that someone like (al-Shishani) could assume overall military leadership," said Charles Lister, Visiting Fellow with the Brookings Doha Center.

The extremist group began as al-Qaida's branch in Iraq, and many of its top leaders are Iraqi. But after it intervened in Syria's civil war last year, it drew hundreds of foreign fighters into its operations in Syria. Now with victories on the two sides of the border, the two branches are swapping fighters, equipment and weapons to an even greater extent than before, becoming a more integrated organization. Its declaration of the caliphate - aspiring to be a state for all Muslims - could mean an even greater internationalization of its ranks.

Alexei Malashenko, an expert with the Carnegie Endowment's Moscow office, said ethnicity is not a major factor in jihadi movements, only dedication to jihad. Al-Shishani "is a fanatic of Islam with war experience, and he obviously has had a strong track record (among fellow fighters)," he said.

Syria's civil war, in its fourth year, has attracted militants from around the world. Some estimates run as high as 10,000 foreign fighters in the country. But the Chechens - hardened from years of wars with Russia in the Caucasus region - are considered some of the best fighters.

Alexander Bortnikov, the head of Russia's Federal Security Service, the main KGB successor agency known under its Russian acronym FSB, said last October that about 500 militants from Russia and hundreds more from other ex-Soviet nations are fighting in Syria.

Al-Shishani, whose real name is Tarkhan Batirashvili, is an ethnic Chechen from the Caucasus nation of Georgia, specifically from the Pankisi Valley, a center of Georgia's Chechen community and once a stronghold for militants.

He did military service in the Georgian army but was discharged after an unspecified illness, said one of his former neighbors, who spoke on condition of anonymity for fear of reprisals. At one point, Georgian police arrested him for illegal possession of arms, the neighbor said. As soon as he was released in 2010, Batirashvili left for Turkey. Georgian police refused to comment.

He later surfaced in Syria in 2013 with his nom de guerre, which means "Omar the Chechen" in Arabic, leading an al-Qaida-inspired group called "The Army of Emigrants and Partisans," which included a large number of fighters from the former Soviet Union. A meeting was soon organized with al-Baghdadi in which al-Shishani pledged loyalty to him, according to Lebanon's al-Akhbar newspaper, which follows jihadi groups.

He first showed his battlefield prowess in August 2013, when his fighters proved pivotal in taking the Syrian military's Managh air base in the north of the country. Rebels had been trying for months to take the base, but it fell soon after al-Shishani joined the battle, said an activist from the region, Abu al-Hassan Maraee.

The Islamic State of Iraq and the Levant entered the Syria conflict in 2013, and initially it was welcomed by other rebels. But rebel groups - including other Islamic militant factions - turned against it, alienated by its brutal methods and kidnappings and killings of rivals, and accusing it of trying to take over the opposition movement for its own ambitions of creating a transnational Islamic enclave. Rebel factions have been fighting against the group since last year in battles that have left thousands dead. Al-Qaida's central command ejected the extremist group from the network.

For the past two months, al-Shishani has led an offensive in Syria's eastern Deir el-Zour province against rival rebels, seeking to solidify his hold on a stretch of territory connected to neighboring Iraq.

In May, some Arab media organizations reported that al-Shishani was killed in the fighting. An activist in Iraq in contact with members of the Islamic State of Iraq and the Levant said al-Shishani suffered wounds in his right arm and was taken into Iraq where he underwent treatment before returning to Syria. He spoke on condition of anonymity for security concerns.

Since then, al-Shishani has appeared multiple times in photos and videos put out by the group. The photos and videos are consistent with the AP's reporting from activists on the ground. In a recent photograph, the young, round-faced al-Shishani, wearing a black cap and beige gown, is seen with a big smile as he examines a Humvee said to have been captured in Iraq and brought into Syria.

Hussein Nasser, spokesman for the Islamic Front coalition group of rebels, said Chechens are among the most feared fighters in Syria.

"A Chechen comes and has no idea about anything (in the country) and does whatever his leader tells him," Nasser said. "Even if his emir tells him to kill a child, he would do it."