An 83-year-old man has collapsed and died of a heart attack after a confrontation with youths in a park.
The man argued with two boys in Hesketh Park in Southport, Merseyside, on Saturday afternoon, police said.
A pine cone was thrown at him during the altercation and soon after getting up from a bench he suffered a fatal heart attack.
He was taken to Southport Infirmary where he was pronounced dead. Police are treating the death as suspicious.
The man, who has not been named, is believed to have asked the youths to stop playing football in a rose garden.
Football is banned in the 12-acre Hesketh Park which is described by Sefton Council as a "horticultural treasure trove".
Insp George Dawson, of Merseyside Police, said: "It is believed that the argument took place at about 1430 BST in a rose garden in the park.
"During the argument it is believed a pine cone was thrown at the pensioner, who was sitting on a bench. A short while later he got up from the bench and collapsed."
Insp Dawson appealed for witnesses and urged people to call Crimestoppers. He said they did not yet have descriptions of the two youths.
A post-mortem examination will be carried out on Sunday.