Three college students from the prosperous suburbs of Birmingham, Ala., were arrested yesterday in the burning of nine Baptist churches last month in rural Alabama. Federal officials said the fires were a "joke" that spun out of control while the students were deer hunting.

After initially setting ablaze five churches in the county just south of Birmingham, two students burned four additional churches days later in more remote areas, hoping to divert investigators, the authorities said.

Two students, Benjamin N. Moseley and Russell L. DeBusk Jr., both 19, from Birmingham-Southern College, were arrested on the campus after admitting their involvement in the fires to federal agents, officials said.

The agents were led to the students by tire tracks at several burned churches, officials said.

Several hours later, the authorities arrested Matthew Lee Cloyd, 20, a student at the University of Alabama, Birmingham, whose mother owns the Toyota 4Runner that left the tracks, federal agents said in an affidavit with the criminal complaint.