Russian opposition leader Alexei Navalny 'poisoned'

Russian opposition figure Alexei Navalny is unconscious in hospital with suspected poisoning, his spokeswoman has said, according to the BBC.

The anti-corruption campaigner fell ill during a flight and the plane made an emergency landing in Omsk, Kira Yarmysh said on Twitter.

She said they suspect Mr Navalny was poisoned by something mixed in his tea. A hospital has confirmed his admission.

Mr Navalny, 44, is a staunch critic of President Vladimir Putin.

In June he described a vote on constitutional reforms as a "coup" and a "violation of the constitution". The reforms allow Mr Putin to serve another two terms in office.