BOSTON -- Eight people, including two firefighters, were injured Friday when a building under construction at a condominium complex exploded in Norfolk.

The incident happened at a building at the Village at River's Edge on Wildwood Road at about 12:30 p.m.

"I live right down the street. I heard a horrendous explosion, and I ran out and saw everything flying in the air," resident Judy Hardy said. "Insulation pieces were flying down the street. I never expected this. I feel terrible for the people who have been hurt."

Three people were taken by medical helicopter to Boston-area hospitals, and the others were taken from the scene in ambulances. Of those injured, two were firefighters, five were construction workers and one person was a resident in the community.

Firefighters worked for more than 90 minutes to rescue a construction worker who was trapped under the debris.

"I was trying to sleep, and I heard a boom and it woke me right up," said one witness who lives about one mile from the scene. "My whole house shook."

Firefighters were working to extinguish a five-alarm blaze that sparked after the explosion. The cause of the blast remained under investigation.

Wrentham-based Di Placido Development Corp. was the company developing the complex.

There have been no safety violations in the past 15 years against the company, according to Occupational Safety and Health Administration records.

The complex is an adult community being built on a 51-acre site near the Norfolk/Millis line.

NewsCenter 5 and TheBostonChannel.com will have more information when it becomes available.