Women's rights activist and presidential candidate Diane Shima Rwigara. Picture: AP

Kigali - Rwandan police on Monday arrested Diane Shima Rwigara, who was barred from standing against incumbent Paul Kagame for the presidency, along with her mother and sister, on suspicion of forgery and tax evasion, a spokesman said.

"They are accused of tax evasion and secondly Diane Rwigara is accused of using fake documents while she was gathering signatures for (her) presidential candidacy,” police spokesman Theos Badege told reporters.

Electoral authorities barred Rwigara from standing in August's presidential vote, saying she had not submitted enough supporters' signatures and some of the names she did sent in belonged to dead people - allegations she denied.