Police say a man caught fire in the parking lot of a 7-Eleven convenience store and gas station in Portland and was rushed to Maine Medical Center Friday afternoon with very serious burns after the flames were extinguished by bystanders.

Investigators with the Portland police and state Fire Marshal’s Office are trying to determine how the man came to be so badly burned, but declined to give out any further information.

EMTs, police and firefighters responded to the store’s parking lot about 1 p.m., said Lt. Robert Martin, spokesman for the Portland police.

The man’s condition was not immediately known. Police also did not immediately classify the incident as either suspicious or accidental.

“We are not releasing any further details at this time except that there is no danger to the public,” Martin said.

State Fire Marshal Joe Thomas said he sent three investigators to assist local police, but so far, they have not established what happened.

A witness, John Pierce, 44, said he was walking down Dow Street to go to the Walgreen’s pharmacy when he saw a pharmacy employee and friend of Pierce’s run across Congress Street holding a fire extinguisher.

Pierce said he watched the pharmacy employee cross the street to a fire between the 7-Eleven gas pumps and a propane tank and put out a fire.

Pierce said he only learned later, when he went into the pharmacy and talked to his friend, that the flames had engulfed a person.

The friend told Pierce that the man was running around, engulfed in flames.

“I presumed it was a gas leak,” Pierce said. “Someone spilled gasoline, something of that nature. I didn’t know it was a person at the time. I just saw it was a fire.”