Islamic State leader Abu Bakr al-Baghdadi has been killed, according to a leading human rights body.

The Syrian Observatory for Human Rights said it had “confirmed information” that Baghdadi was dead, after weeks of conjecture over the leader’s death.

“[We have] confirmed information from leaders, including one of the first rank, in the Islamic State in the eastern countryside of Deir al-Zor [in Syria],” Rami Abdulrahman, the director of the British-based war monitoring group, said.

Mr Abdulrahman said the group’s sources in Syria’s eastern town of Deir al-Zor had been told by Islamic State contacts that Baghdadi had died, but that they did not know when or how.

However, the US-led coalition battling Islamic State says it still has no concrete information on Baghdadi and so was unable to confirm the news.

“Despite all the helpful reports to us from every source imaginable, I’m unable to confirm or deny either where he is or whether he is alive or dead,” Lieutenant General Stephen Townsend told a news briefing on Tuesday.

“Let me just say for the record my fervent hope is it is the latter.”

Russia’s defence ministry said it may have killed Baghdadi when one of its air strikes hit a gathering of Islamic State commanders on the outskirts of the Syrian city of Raqqa, but Washington said it could not corroborate the death, and Western and Iraqi officials have been sceptical.

Reuters could also not independently verify Baghdadi’s death.

Baghdadi’s death, which has been frequently reported since he declared a caliphate from a mosque in the Iraqi city of Mosul in 2014, is one of the biggest blows yet to the jihadist group, which is trying to defend shrinking territory in Syria and Iraq.