Fires gutted four multimillion-dollar model homes in a Seattle suburb on Monday, and authorities found a sign purportedly left by ecoterrorists that mocks claims that the homes were environmentally friendly.
"Built Green? Nope black!" said the spray-painted sign that bore the initials of the radical environmental group Earth Liberation Front.
Explosive devices were found in the homes, and crews were able to remove them, said Fire Chief Rick Eastman of Snohomish County District 7.
The FBI was investigating the fires as a potential domestic terrorism act, said FBI spokeperson Rich Kolko in Washington, D.C.
The fires started at the "Street of Dreams," a strip of unoccupied, furnished luxury model homes where developers show off the latest in high-end housing, interior design, and landscaping. The homes are later sold.
No injuries were reported in the fires, which began before dawn in the wooded subdivision and were still smoldering by midmorning.
The homes are in a development near the headwaters of Bear Creek, which is home to endangered chinook salmon. Opponents of the development had questioned whether the luxury homes could pollute the creek and an aquifer that is a drinking water source, and whether enough was done to protect nearby wetlands.
The sign, a sheet with red scraggly letters, said "McMansions in RCDs r not green," a reference to rural cluster developments.
One of the people involved in the project said the homes used "green" techniques, such as water-pervious sidewalks, superinsulated walls and windows, and products made with recycled materials.
Advertising for last summer's "Street of Dreams" show focused on the environmentally friendly aspects of the homes, which were smaller than some of the houses featured in years past.
"It's very disappointing to take a situation where we're tying to promote good building practices—"Built Green" practices—and that it's destroyed," said Doug Barnes, the Northwest division president of Centex Homes in Kirkland and the immediate past president of the Master Builders Association of King & Snohomish Counties.
The homes that burned were between 4,200 and 4,750 square feet (between 390 and 440 square meters) in size, with prices up to nearly two million U.S. dollars.
The Earth Liberation Front, or ELF, is a loosely organized collection of radical environmentalists that authorities claim have committed other arsons in the Northwest.
A woman is currently trial in Tacoma, Washington, for a suspected ELF fire at the University of Washington in 2001. Briana Waters, a 32-year-old violin teacher, is accused of serving as a lookout while her friends planted a devastating fire bomb.
The fire is one of the most notorious in a string of arsons that investigators say were perpetrated from the mid-1990s to 2001 by ELF.
No one was hurt in that incident, but the university's Center for Urban Horticulture was destroyed and rebuilt at a cost of seven million U.S. dollars.
The center was targeted because the ELF activists mistakenly believed researchers there were genetically engineering trees, investigators said.
Associated Press writer Lara Jakes Jordan in Washington, D.C., contributed to this report.
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