MOSCOW, -- A Russian air strike in Syria killed the spokesman of the Daesh group, Abu Muhammad al-Adnani, the defence ministry in Moscow hsaid.
The Amaq news agency, linked to Daesh, earlier acknowledged that al-Adnani had died in Aleppo province.
Russia says Adnani died on Tuesday in a Su-34 bomber raid on the village of Umm Hawsh.
The US had earlier said that one of its aircraft had targeted Adnani in the city of al-Bab.
Adnani was one of the Daesh group's most high-profile figures, with a $5m bounty on his head.
The US said he had "co-ordinated the movement of Daesh fighters, directly encouraged lone-wolf attacks on civilians and members of the military and actively recruited" new members.
His death is considered a major blow to the jihadist group, which has suffered a series of military reverses in both Syria and Iraq.
Umm Hawsh is 24km (15 miles) north of Aleppo and 28km west of al-Bab.
Russia's defence ministry said Adnani was one of up to 40 militants killed in air strikes there by the Su-34 bomber.
It said its information had been confirmed "through several intelligence channels".
This is the first time Moscow has said it has killed a key Daesh leader.
However, Pentagon spokesman Peter Cook said that "we have no information to support" Russia's involvement.
Another US official said that the US strike had been carried out by a Predator drone, which fired a Hellfire missile at a car believed to be carrying Adnani.
Adnani - who was also the group's spokesman - was "martyred while surveying the operations to repel the military campaigns against Aleppo", Amaq said, without giving details about how he died.
One of the group's founder members, Adnani was born Taha Sobhi Falaha in the northern Syrian town of Banash in 1977.
In June 2014, he formally declared the establishment of the Daesh caliphate stretching across parts of Syria and Iraq under the leadership of Abu Bakr al-Baghdadi.
Source: Nam News Network