Seattle ? Two radio station towers near Seattle that have generated intense local opposition were toppled early Friday in an act of sabotage that bore the initials of the radical Earth Liberation Front.

The towers for KRKO-AM — one of which was 349 feet tall — were torn down because of health and environmental concerns, according to an e-mail from the North American ELF Press Office, which has represented the shadowy group in the past.

“We have to weigh our priorities, and the local ecosystem in Everett, along with the local residents, do not need additional sports news radio station towers that come at the expense of reduced property values and harmful radio waves,” ELF press office spokesman Jason Crawford said in the e-mail.

The ELF is a loose collection of radical environmentalists that has claimed responsibility for dozens of attacks since the 1990s. A banner that bore the initials of the ELF was left at the scene, authorities said.

The FBI has taken over as lead investigator in Friday’s incident, and agent Marty Prewett said authorities haven’t found any evidence that other individuals or groups besides the ELF were involved.

The towers apparently were taken down with a track hoe, a piece of heavy construction equipment that was already on the site, Prewett said.

Andy Skotdal, KRKO owner and general manager, said part of the tower fell onto the track hoe and damaged the scoop mechanism.

“Whoever did it is lucky they didn’t get killed,” he said.

Skotdal did not immediately have a damage estimate, spokeswoman Lora Lee said Friday afternoon.

The ELF’s Web site featured a picture of one of the towers lying on its site with the caption “Earth Liberation Front Topples Two Radio Station Towers in Snohomish County, WA,” followed by the words: “Details coming soon.”

Crawford told the AP by telephone he believed more than one person was involved. He said he had not spoken directly with anyone who claimed to be involved but received some e-mail from what appear to be locals who support the action.

The towers belonging to KRKO — a family-owned station in Everett, about 25 miles north of Seattle — have prompted complaints from neighbors of interference from radio signals on home telephone and intercom lines. The site for the towers is in the town of Snohomish, about eight miles southeast of Everett.

The station’s plans to increase its transmission capacity by building more towers on the site have been embroiled for more than a decade in appeals and litigation over issues ranging from trumpeter swan habitat to potential health hazards to humans.