The so-called Islamic State leader Abu Bakr al-Baghdadi may have survived a Russian airstrike in May, according to a top US military commander.

"Do I believe he's alive? Yes," said Army Lt. Gen. Stephen Townsend, the US commander of forces fighting IS in Iraq and Syria. "There are also some indicators in intelligence channels that he's alive."

Townsend, who is ending his year in command in Baghdad in a week's time, said he didn't have any information regarding al-Baghdadi's whereabouts. But added he could be hiding in the Middle Euphrates River Valley, stretching from the city of Deir el-Zour in eastern Syria to the town of Rawa in western Iraq.

Read more: Who is Abu Bakr al-Baghdadi?

al-Baghdadi's last public appearance was at Mosul's Grand al-Nuri in 2014. 'IS' destroyed the mosque in June.

'Not worth all the trouble to try and capture him'

The militia leader, with a $25 million (21 million euro) US bounty on his head, has been reported dead on numerous past occasions.

He has not been seen in public since his appearance at the Grand al-Nuri Mosque in Mosul in 2014, when he proclaimed himself the leader of the "IS caliphate.”

Russian officials said in June there was a "high probability" that al-Baghdadi died in a Russian airstrike on the outskirts of Raqqa, Syria, a month earlier.

Britain-based conflict monitor Syrian Observatory for Human Rights said later that it had it has "confirmed information" that the IS leader was dead.

Speaking to reporters at the Pentagon from his headquarters in Baghdad on Thursday, Townsend said US and coalition forces are hunting for al-Baghdadi.

"When we find him, I think we'll just try to kill him first," he said. "It's probably not worth all the trouble to try and capture him."

ap/sms (AP, AFP)