OMAHA, Neb. (AP) _ The Hell's Angels motorcycle club was largely put out of the illicit business of methamphetamines trafficking with the arrests of 15 people in the Omaha area and another in California, an FBI agent says.

''We have made a significant impact on their ability to conduct illegal activity in this area,'' said Dennis Aiken, assistant special agent for the FBI in Omaha.

Surrounded by confiscated rifles, a .22-caliber automatic pistol, $800,000 worth of drugs, $200,000 in cash as well as Hells Angel's jackets and posters, Aiken said a two-year investigation culminated in simultaneous raids Wednesday on 14 locations, including the club's headquarters in Omaha.

A Rottweiler guard dog was killed after it attacked an officer at the clubhouse. One man at the clubhouse resisted arrest, but the other searches and arrests were conducted without incident, Aiken said.

''We consider this group to be a major center in the trafficking of methamphetamines,'' Aiken said at a news conference. Hell's Angels clubs have played a major role in methamphetamine traffic in the United States, he said.

Many of the fewer than 50 club members in the Omaha area are now in jail, Aiken said. Everyone arrested in the Omaha area Wednesday was a Hell's Angel club member or a club associate, Aiken said.

The investigation continued and it wasn't known how much contraband and money would eventually be confiscated, Aiken said.

Charges included interstate and foreign travel in support of racketeering enterprises, money laundering, manufacturing and distribution of a controlled substance and felony possession of a firearm, an FBI press release said.

Eleven of the 16 people arrested Wednesday in or near Omaha and in Long Beach, Calif., had been named in a federal grand jury indictment issued Monday, Aiken said. The five others were arrested on charges of drug possession based on evidence obtained during the raids, he said.

Larry Holmquist, an FBI spokesman, would not comment on the connection between the arrest in California and the others here.

Douglas County Sheriff Dick Roth said the suspects had been investigated as far back as 1978.

''We have had tons of intelligence on these people's actions over the years,'' Roth said.

A cooperative effort that included the FBI, Nebraska State Patrol and the federal Drug Enforcement Administration used electronic surveillance such as wire intercepts, Aiken said. He refused to say whether undercover agents played a role.

Homes and businesses were searched in Omaha, in Valley to the west and in Council Bluffs, across the Missouri River in Iowa, the FBI said.