A day after two men detonated an explosive device inside a Mississauga, Ont. restaurant, witnesses and family of the restaurant’s owners are expressing their shock about what happened.

On Thursday night at about 10:30 p.m., two men with their faces covered entered the Bombay Bhel restaurant in central Mississauga and detonated an improvised explosive device. They then fled into a nearby residential area.

Fifteen people were injured in the explosion, three of them critically. All 15 victims have since been released from hospital.

“They were bloody all the way through,” one witness told CP24. “There was massive blood loss.”

Two separate birthday parties were underway at the time of the bombing. Several children were inside, but police said none of them were injured.

“Somebody said that they were literally (cutting) the cake when it happened," said Mona Jagota, a friend of the restaurant’s owners and a fellow business owner in the plaza.

Jagota was in the area at the time of the explosion and described the police response to the incident.

"There were like lights flashing, lights everywhere,” she said. “There were more than 20 police cars, fire trucks (and) ambulances.”

Bombay Bhel is a family-run business that’s been in operation for more than 30 years. Derek Patterson, the son-in-law of the restaurant’s owners, said his family is still in disbelief.

“They’re not doing well,” he told CTV Toronto. “It’s a big shock. Nobody expects to go into work and have a bomb go off.”

“They’re very concerned about their customers (and) the people who were hurt.”

On Friday, several businesses in the plaza were closed for the day as the police investigation continued.

Witnesses were allowed to return and pick up their vehicles. Some offered a first-hand account of what it was like inside and around the restaurant when the bomb went off.

“I could see my brother dying in front of me,” one witness told CP24. “He was full of pain.”

Rafael Conceicau was in a restaurant across the parking lot from Bombay Bhel when he heard the explosion.

“Everything was destroyed,” he said. “Many people were screaming. They were trying to run out from the restaurant."

Police are still searching for the two suspects and said there’s nothing to indicate this might be an act of terrorism, but they’re not ruling anything out.

With files from CTV Toronto and CP24