Fundraiser set up for Year 7 pupil Ryan Heffernan, 12, who died at Shoeburyness High School in Essex

The last words of a 12-year-old boy who died suddenly at school were "I love you", according to people fundraising in his memory.

Ryan Heffernan died after what police called a "medical emergency" at Shoeburyness High School in Essex at about 1.20pm on Monday.

The Year 7 pupil was treated by paramedics at the scene and taken to Southend University Hospital but could not be saved.

A fundraiser set up to provide financial support for his funeral has already raised more than £14,000.

It was set up by Charlene Mullaly, who described Ryan as a "kind-hearted, happy, full-of-life young boy".

"Monday morning he left for school, healthy and happy, saying 'I love you' to his family (This was the last thing he said to them)," Ms Mullaly wrote on the fundraising page.

"He was only in his first year of senior school, a Year 7 student on his lunch break when he was sadly taken."

The page says that the fundraiser has been set up on behalf of Catherine Heffernan.

Ms Mullaly added: "No parent should have to endure this pain. I cannot begin to imagine how hard it must be to process.

"I am deeply saddened by what has happened as I know many are shocked and upset.

She added she wanted to raise money "so that he can have the best send-off, and to help the family have the time they need in order to heal with spending quality time supporting his two sisters, in memory of Ryan".

After Ryan's sudden death, police moved to quash rumours that a knife had been involved, clarifying that it "was a medical emergency only and no other persons or weapons of any kind were involved".

They added that they were treating his death as unexplained and preparing a report for the coroner.

The school said it had brought in specialist support to help pupils and staff who were involved in the incident. 

"Our thoughts are with the family at this time and along with the police we are doing everything we can to support them during this very difficult time," said a spokesman on Tuesday.