Russian opposition politician Alexei Navalny's health has reportedly deteriorated drastically in the past two weeks. "We do not rule out that during his time in prison he may have been poisoned," his spokesperson Kira Yarmysh says.

Navalny was called an ambulance on Friday after suffering acute stomach pains. He has lost eight kilos in the last 15 days in the prison's punishment cell, according to his press spokesman. He was released from the prison on Friday, but sent back there on Monday for the 13th time.