RESTING SERENELY ALONG Bremerton’s waterfront, the nuclear submarine USS Alaska presents a foreboding silhouette. Two football fields long, the sub is being refitted with 24 advanced Trident II missiles, each capable of wiping a small country off the map. As part of America’s nuclear deterrent force, the $1.2 billion machine, in port or at sea, operates under the highest security.

So who sabotaged it? And why? How did someone get inside one of America’s most lethal nuclear weapons and destroy some of its equipment last summer? And were we—Bremerton, Seattle, the world—ever in peril?

The Navy, which has been mum about the incident for months, now says it has the answers, beginning with it was an inside job.

“We have an Alaska crew member in custody,” Navy spokesman Lt. Kevin Stephens said last week. Although he termed the sabotage a national security violation, “neither any of the personnel on the sub nor the public were at danger,” he says.

The Navy identified the sailor as Petty Officer 2nd Class Ernesto G. Cimmino, 23, of Scotia, N.Y., who joined the Navy in January 1997 and became one of the Alaska‘s 300 crew members two years ago. He is being charged with 23 counts of sabotage, five counts of larceny, and several other Military Code offenses including conspiracy and wrongful use of a controlled substance. Stephens would not reveal the exact damage to the sub, which was commissioned in 1986. But sources at the Puget Sound Naval Shipyard in Bremerton, where the Alaska is undergoing an 18-month missile conversion, say the damage included spliced power cables, which could have affected the ship’s navigation had it been under way.

It may be the first such incident aboard a US nuclear sub, though Navy officials wouldn’t confirm that. “It certainly doesn’t come up that often,” says Stephens, public information officer for Naval Submarine Base Bangor, the Alaska‘s home port, who was unaware of any similar incidents.

Navy officials waited until November to publicly reveal the damage, said to have taken place in August and termed “deliberate.” The suspect was arrested a week later; however, there was scant news coverage. The Naval Criminal Investigative Service quietly picked him up the day after Thanksgiving at Sea-Tac Airport, returning from a holiday trip, Stephens says.

The suspected crewman now waits in “pretrial detention” at the Bangor base brig. He faces an Article 32 indictment hearing later this month, during which evidence will be presented to officially charge him, Stephens says.

This was at least the third incident involving threats to the Alaska since its April arrival at the shipyard. A phoned-in bomb threat was made in May. Earlier, concerned about a possible confrontation with anti-nuke demonstrators, the Navy kept the sub’s Bremerton arrival time a military secret.

“I don’t know if they suspected us, but we didn’t do anything, including the bomb threat,” says Jackie Hudson, a member of the Kitsap County protest group Ground Zero. “We have only peacefully demonstrated to make people aware of the threat these subs pose to us.”

Despite the Navy’s reassurances of no harm, Hudson is nonetheless concerned about the threat posed by sabotage.

“It makes us wonder even more,” she says, “about the security surrounding these dangerous weapons.”