INDIAN HEAD, Md. (AP) – A dozen expensive homes under construction were burned down early Monday in a suburban Washington housing development that had been criticized by environmentalists because it is next to a nature preserve, officials said.

An FBI agent said the fires may have been set by environmental extremists.

Beside the dozen homes destroyed, 29 others were damaged near the state’s Mattawoman Natural Environment Area. Damage was estimated at a minimum of $10 million.

Faron Taylor, a deputy state fire marshal, said investigators believe fires were set in at least four of the homes, which were priced at $400,000 to $500,000. Taylor refused to say what led investigators to conclude it was arson.

“At this point, our knowledge of the methodology is shared by us and the perpetrator, and we don’t want to share that with anyone else,” Taylor said. “We’re not going to tip our hand.”

A Sierra Club report had called the development “quintessential sprawl” because it is far from existing infrastructure and “threatens a fragile wetland and important historical sites near the Chesapeake Bay.”

After the fires, the Sierra Club issued a statement saying it “strongly condemns all acts of violence in the name of the environment.”

FBI spokesman Barry Maddox said agents were on the scene and would investigate whether the fires were ecoterrorism.

“Anything and everything will be considered, but we’re not labeling this anything other than suspicious fires,” Maddox said.

The fires were reported before 5 a.m., drawing firefighters from four counties to the subdivision about 25 miles south of the nation’s capital. The houses, on lots of about a quarter-acre each, were spread across 10-acres, Taylor said.

Jacque Hightower told WRC-TV, “We were going to settlement in about two days, and we woke up this morning and looked at the news and my wife just screamed ‘Our house is on fire,’ so I just came down today to try to find out what’s going on.”

Taylor said the fire would be investigated by agents from the Maryland fire marshal’s office and the federal Alcohol, Tobacco, Firearms and Explosives, which is routinely brought in to help investigate large fires.

Environmental groups and some local residents sued the Environmental Protection Agency and the Army Corps of Engineers last year, claiming they had violated the Clean Water Act by granting permits that allowed construction at the site.

In July, a federal judge denied a request for an injunction against construction but ordered the Army Corps to better explain its decision authorizing the sewer line and road in the subdivision. The Army Corps has appealed that decision.

Patricia Stamper, an Indian Head resident and a plaintiff in the lawsuit, said the development would cause major damage to one of the last undisturbed magnolia bogs in the country.

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