(Reuters) - Authorities in two Russian regions have blocked the Telegram messenger because of concerns that the app could be used by enemies, a regional digital development minister was quoted as saying by the TASS state news agency on Saturday.

Dagestan and Chechnya are mainly Muslim regions in southern Russia where intelligence services have registered an increase in militant Islamist activity.

"It (Telegram) is often used by enemies, an example of which is the riots at the Makhachkala airport," said Yuri Gamzatov, Dagestan's digital development minister, adding that the decision to block the messenger had been made at the federal level.

Gamzatov was referring to an anti-Israel riot in Dagestan in October 2023, when hundreds of protesters stormed an airport to try to attack passengers arriving on a plane from the Jewish state. No passengers were injured, and authorities have prosecuted several people over the incident.

News of the plane's arrival had spread on local Telegram channels, where users posted calls for antisemitic violence. Telegram condemned the attack and said it would block the channels.

Telegram did not immediately respond to a request for comment on the blocks in Russia.

Based in Dubai and founded by Russian-born Pavel Durov, the messenger has nearly 1 billion users and is used widely in Russia, Ukraine and other former Soviet republics.

Moscow tried but failed to block Telegram in 2018 and has in the past demanded the platform hand over user data. Durov is under formal investigation in France as part of a probe into organised crime on the app.

Gamzatov, the minister in Dagestan, said Telegram could be unblocked in the future, but encouraged users to switch to other messengers in the meantime.

(Writing by Lucy Papachristou, Editing by Timothy Heritage)