Three people were injured after lightning struck in Brampton, Ont., on Wednesday. (Sean Magennis/CBC)

The father of a five-year-old boy struck by lightning in a Brampton, Ont., park said his son is still in critical condition and has been drifting in and out of consciousness.

Oral Caines said he has been able to talk to his son, Kyus Caines, who is at the Hospital for Sick Children in Toronto.

“I wish it was me instead of you" Caines said he told his son.

Oral Caines said he has been able to talk to his son, Kyus Caines, who is at the Hospital for Sick Children in Toronto. (CBC)

Kyus, his mother Dulce, 26, and Kyus's three-year-old friend were on a soccer field on Wednesday at Centennial Park in Brampton, Ont., just west of Toronto, when they were hit by what one witness described by as a "fireball."

The mother remains in fair but stable condition at Brampton Civic Hospital.

Oral Caines said the three were out at the park when they saw clouds coming in and decided to go home. As they were walking through the field, he said, lightning struck.

Caines said his son was the one directly hit by lightning, and the other two were beside him.

Outside Sick Kids on Thursday morning, emergency room physician Seen Chung said he couldn't comment directly on the injuries to the boys but indicated these types of injuries can be very serious.

"The long-term effects are going to be based upon the injury that's occurred, the type of injury and what organs are involved. And [it is] the severity of the injury that's going to determine if there will be a long-term injury," said Dr.

Dr. Chung said that while children tend to be more resilient — and sometimes can recover faster than adults — in cases of lightning injuries there's really no difference in recovery times.

The lightning struck at about 2 p.m. on Wednesday.

Allan Hughes, whose backyard is next to the park, said he was watching the Toronto Blue Jays game on television when he was startled by an "abnormally loud bang." He then heard a woman screaming for someone to call 911.

Hughes said he ran out to try to help and discovered one of the boys lying in the field not moving.

The boys' clothes had been shredded off due to the impact of the lightning strike, Hughes said.

"[It] was just the worst, terrifying thing I've ever seen," a distraught Hughes told CBC. He tried to do CPR on one of the boys.

"His little eyes were wide open, blue eyes just staring at me."

Connie Denbok, whose home also borders the soccer field, said it was partly cloudy at the time with no rain, but there was a distant rumbling of thunder.

Then Denbok said she saw "what looked like a fireball outside my window," followed immediately by a clap of thunder and screaming.

She hurried to the field and sat with the three who appeared unhurt, though she said they were understandably quite upset.

Although there was a forecast 40 to 60 per cent chance of thunderstorms in the Toronto area Wednesday, there were no specific watches or warnings issued for Brampton, according to CBC meteorologist Nick Czernkovich.

"This particular thunderstorm didn't meet the warning criteria, but it doesn't mean it couldn't be dangerous," said Czernkovich. "Every thunderstorm can be dangerous and should be treated with caution."

The No. 1 safety tip is to get indoors, he added.

Environment Canada meteorologist Geoff Coulson said the storm was considered "weak and a very localized event" that only produced 15 to 20 flashes of lightning.

"Every thunderstorm has lightning associated with it," Coulson said. "There would be too many warnings put out, so that is why we reserve watches or warnings for only the most severe situations."