PROVO — Fires that caused an estimated $30,000 in damage to a Brigham Young University facility early Thursday may be the second attack recently against BYU by Animal Liberation Front activists, authorities say.

Two fires were set in sheds used by campus grounds crews near animal science buildings — one containing recycling materials, the other two small tractors. The letters "ALF" and other related phrases on buildings and trucks were found near the site of the fires at BYU's Ellsworth Farm, located at 2230 North and University Avenue.

A man living nearby noticed the smoke around 3:30 a.m. and called 911. BYU police and the Provo fire department responded to the blaze and are investigating in cooperation with the FBI, the federal Bureau of Alcohol, Tobacco and Firearms and the U.S. Department of Homeland Security. Investigators said Thursday they have no witnesses or promising leads as of yet.

The FBI and Department of Homeland Security are involved because ALF arsons are considered terrorist attacks.

"It is considered a terrorist attack because of the nature of the attacks that the ALF and — I don't think it'd be too far off calling it a sister organization — ELF, the Earth Liberation Front, employ in arsons, which obviously cause a threat to human life, liberty and property," said special agent Mike Anderson, Provo FBI supervisor.

According to an ALF Web site, www.animalliberationfront.com, the mission of its members is to "carry out direct action against animal abuse in the form of rescuing animals and causing financial loss to animal exploiters, usually through the damage and destruction of property."

Thursday's incident is not the first attack on BYU's Ellsworth farm, according to FBI agents investigating the case. On May 17, activists broke into the building and released six rabbits and seven birds, wrote some minor graffiti and spray-painted the windshield of a BYU vehicle.

Activists claimed credit for the earlier incident and posted pictures anonymously via the Web site of Bite Back Magazine, which chronicles ALF "direct actions" around the world. "We talked a lot about saving the animals from the labs and finally decided to act," the posting said. "Sooner or later someone had to stand up and try to do what's right for these animals."