Several pupils have been expelled from one of the country's top rated grammar schools after allegations that students took M-CAT and Ketamine during their lunch break.

It is understood that three sixth formers were expelled from Caistor Grammar School before last week's half term, while another three have been suspended.

A source said that a sixth former was found taking class B drugs during their lunchtime break in woods near the school.

Founded in 1630 - Caistor Grammar boasts Strictly Come Dancing winners Kevin and Joanne Clifton, and Dawn French, among it's former pupils.

In 2017 it was named as one of the best selective state schools in the country - and in 2018 it was rated the best secondary school in Lincolnshire by the Real School Guide after finishing top of the county's league tables for many years.

According to a local report, a student was found in possession of ketamine, a hallucinogenic and M-CAT, a powerful stimulant.

Head teacher Alistair Hopkins made the decision to expel the three students before last week's half term break after an investigation and Humberside Police had been informed.

He said he will enforce the "most severe sanctions" and said the school, which opened in 1630, is a "drugs-free zone".