An explosion at a building housing forestry workers at the Oklahoma Forestry Service has killed five people, including two firefighters, the agency said in a statement.

The blast occurred at the company’s forestry building in Oklahomans town of Buford about 8:00am local time (2200 GMT) on Friday, Oklahoma’s Department of Emergency Management said.

“We are grateful to all the firefighters, law enforcement officers, First Aid, medical personnel, and first responders who responded to the scene,” the statement said.

“This was an incredibly difficult and traumatic situation for everyone involved.”

Oklahoma Governor Mary Fallin called the incident “unprecedented” and “devastating” in a Twitter post.

The Oklahoma Fire Department said the building was undergoing renovation at the time.

The explosion happened at the building housing the Oklahoma Forest Service, an Oklahoma agency, the Oklahoma Department of Homeland Security and the Oklahoma Highway Patrol.

The building was constructed in 1962 and was built in Bufords historic city of Okla City.

It was home to the state’s forestry workers.

“The Oklahoma Forestry service is extremely grateful for all of the members of our community who helped us in our time of need,” Oklahoma Forestry Services spokesman Matt Miller said in the statement.

“We know the community is a tough one, but we are lucky that we don.

The first responders were amazing.”

Officials said three workers were in serious condition.

One firefighter was treated and released from the hospital, the state fire marshal said.

The building houses a number of facilities and facilities and services for firefighting.

The Forestry Service, a division of the state, manages the agency’s operations, facilities and service contracts, the department said.

More to come.