A serial bomber with a fascination for wood is the likely suspect in the bombing this afternoon at the offices of a timber industry loobying group that killed one person, the FBI said.

The mail bomb appeared to be the work of the so-called Unabomber, who is responsible for 15 previous bombings around the country in the past 17 years, said FBI Special Agent Richard Ross.

The special federal Unabom task force from San Francisco arrived this afternoon and is taking over the case, Ross said.

"The similarities in the forensics preliminarily reviewed at the crime scene strongly suggest the Unabomber," Ross said tonight.

This would be the third death attributed to the Unabomber, a name that refers to the bomber's tendency to target universities and airlines. The attacks have injured 23.

No one claimed responsibility for the bombing at the California Forestry Association office four blocks from the Capitol. The executive who opened the package was killed in the explosion.

Several Unabom victims have been in Northern California, including a Sacramento computer store owner who was killed outside his business in 1985.

Investigators say the Unabomber appears to be fascinated with wood. Some of his bomb parts were carved out of wood, one victim was named Wood, and twigs have been included in a bomb. His last victim, New Jersey advertising executive Thomas Mosser, killed at his home in December, lived on Aspen Drive.

The forestry association lobbies on behalf of wood products companies and timber owners.

Police Chief Arturo Venegas said there was no indication the bombing was connected to last week's blast at the Oklahoma City federal building.

The small, heavy package was delivered to the association in the day's mail, said police spokesman Michael Heenan. It was addressed to a specific person in the office, Heenan said, but he declined to say who.

The victim was identified as Gilbert B. Murray, an association lobbyist who lived in suburban Roseville. The bomb blew up just after 2 p.m. as Murray, who was married and the father of three, was opening it.

"It blew doors out. It blew windows out. There is a lot of debris in the hallway. . . . There is a lot of glass and ceiling tiles on the floor," said Fire Department Division Chief Jan Dunbar.

No warning was sent to the association before the package arrived wrapped in brown paper and about the size of a shoebox, Heenan said.

He said five other employees were in the office when the bomb went off in the reception area, but no one else was injured. A pregnant woman was taken to the hospital as a precaution.

Bruce Knadler, a construction worker who was outside when the bomb went off, said he saw the pregnant woman walk outside, trailed by clouds of smoke.

"We were standing in the street and heard a large, hollow boom," Knadler said.

The California Forestry Association is a nonprofit trade group representing wood products companies and commercial forest landowners. In 1993, it filed a petition seeking to remove the northern spotted owl from the federal endangered species list.