A dad whose 12-year-old son died during a school swimming session wants a law to stop such a tragedy happening again.

Grieving Mark King is calling on MPs for legislation to ensure defibrillators are installed in all public places which must have a fire extinguisher.

Mr King has dedicated his life to the cause after he lost his son Oliver to ­sudden arrhythmic death syndrome.

The Oliver King Foundation charity has raised enough for 4,200 ­defibrillators in public places and to train more than 60,000 people how to use them.

Mr King said to date they have been used to save at least 40 lives.

Had one been in place at Liverpool’s King David High School in March 2011, Oliver may still be alive.

The promising footballer, who dreamed of playing for Everton FC, had to wait 24 minutes for a ­defibrillator before the ambulance arrived.

The dedicated dad has raised enough money to fund 4,200 defibrillators and has saved at least 40 lives since 2011 
Budding footballer Oliver King had an undiagnosed heart condition 

The device uses electric shocks to try to restore a regular heartbeat. But Mr King said: “After four minutes chances of survival fall 80 per cent.”

Oliver had an undiagnosed heart condition and SADS kills 12 people under 35 every week in Britain.

The boy’s death shattered Mr King. He said: “There’s one word that comes with this, when you get that phone call, it is devastation. That never goes away.” But he said: “These lives have got to stop being lost.”

Mr King, now 57, said: “The law states that all ­public buildings have to have a fire ­extinguisher, let’s do the same with defibrillators, it will save lives.”

Oliver King, left, with his younger brother, Ben who is now 16

Now he has won the backing of 250 cross-party MPs in calling for a law change.

Mr King said: “Almost every other country has this. France has just done it but we’re the last, once again. Oliver’s heart ­attack came out of the blue.

“He seemed healthy and we couldn’t ­understand why. As a dad I couldn’t get my head around it.

“It turned out he had this genetic condition that affects around 12 young people a week.

“It is to do with the ­electrical system in the heart not working properly. The only thing that can restart it is a defibrillator. No amount of CPR will work.

“As a dad I can’t sit back and do ­nothing if I could help others.”

Car salesman Mr King said: “Ideally we would want defibrillators in every public building by 2020. And for them to be placed by the fire extinguisher.“We are fighting for the government to legislate for this. It shouldn’t just be in schools but in ­community centres, sports halls, libraries, everywhere. We’ve ­lobbied MPs asking them to become defibrillator champions.

“I’ve ­travelled the ­country, from Liverpool to London, helping install defibrillators and train people to use them. I want Oliver’s legacy to be ­defibrillators in all public buildings. It will save so many lives.”

In 2014, former Bolton Wanderers player Fabrice Muamba launched a campaign for more defibrillators in public places. Two years earlier he survived a cardiac arrest on the pitch during an FA Cup game.