Ruth Davidson has also been under fire over the ‘rape clause’ in a cap on child benefits

The Scottish Conservative party was accused by the SNP yesterday of being riddled with “systematic extremism” after several Tory council candidates were engulfed by racism allegations.

Ruth Davidson, the Scottish Conservative leader, was challenged to launch an internal inquiry following the suspension of three party members for racist and anti-Islamic rants on social media.

Others have been criticised for sharing online posts by far-right groups such as Britain First and the English Defence League.

Yesterday, the SNP said Davidson needed to “get a grip” on the racism scandal engulfing the Scottish Conservatives. “This isn’t a case of a couple of rogue candidates slipping through the net; it’s systemic extremism at the very heart of Ruth Davidson’s party,” a spokesman said.

“As a matter of urgency,