Sadly, the football legend had died by the time help arrived. Emergency responders tried to revive him but it was too late.
An autopsy is now expected to confirm that the cause of death was the heart attack.
He reportedly died around midday, local time.
In Argentina, President Alberto Fernandez has already declared three days of national mourning in honour of the football legend.
What Maradona wanted engraved on his tombstone
While still alive, Maradona expressed what he wanted to have engraved on his tombstone.
In a bizarre TV interview which aired 15 years ago, during which Maradona quizzed himself, he said that getting old with his grandchildren would mean "a peaceful death" for him.
"Thanks for having played football because it's the sport that gave me most happiness and freedom and it's like having touched the sky with my hand," Maradona said.
"Thanks to the ball. Yes, I would put on the tombstone ...'Thanks to the ball.'"