The son of a Premier League football star reportedly stabbed 15 pupils at one of the UK's top schools with a diabetes pen on 5 February, 2015. As a result, the pupils underwent HIV and hepatitis tests.

The boy, who has not been named, thought the blood-sugar testing device which he found on a classroom desk was an electric shock toy when he used it to poke his fellow school mates. All of them have now taken tests for HIV and hepatitis B and C, according to The Sun.

"It's been dreadful. The whole school is very upset about it. I should imagine the boy is absolutely distraught – along with everyone else concerned," a source told The Sun.

The boy along with his 14-year-old friend have been expelled over the prank gone wrong. A school spokesman told the paper: "We can confirm that an incident took place at the school [in February 2015] involving a diabetic testing pen.

The incident was extremely concerning and as soon as we became aware of it all parents of pupils involved were contacted immediately and given the advice received from public health experts. While the risk of infection was low or negligible, children affected were advised to have blood tests all of which proved negative."

Surrey Police said they had been made aware of the 5 February incident and no further action was required.