Eighty-seven primary school pupils in South Africa have been discharged from hospital a day after eating biscuits laced with cannabis, known locally as “space cookies”.

Three of the students from Pulamadibogo Primary School in Soshanguve, north-west of the capital, Pretoria, are still receiving treatment, the provincial education authorities say.

They had all experienced nausea, stomach cramps and vomiting before being rushed to hospital on Wednesday after eating the snacks sold by a street seller outside the school premises.

It is unclear if the vendor is to face charges.