SAN DIEGO -- A Navy petty officer opposed to the war in Iraq refused to board his ship Monday as sailors and Marines deployed for the Persian Gulf.

Petty Officer 3rd Class Pablo Paredes, 23, said he has opposed the war since its inception. Until recently, the weapons-control technician said he did not feel he had a direct role in the war. Two weeks ago, however, he said he was involuntarily transferred to the amphibious transport USS Bonhomme Richard, which ferries Marines to Iraq.

"I don't want to be a part of a ship that's taking 3,000 Marines over there, knowing a hundred or more of them won't come back," he said. "I can't sleep at night knowing that's what I do for a living."

Paredes of the New York City borough of the Bronx said he joined the Navy in 2000 and has 20 months left on his six-year enlistment. He said he was stationed previously in Japan.

He said he was young and naive when he joined the Navy and "never imagined, in a million years, we would go to war with somebody who had done nothing to us."

Paredes was at the ship's pier at Navy Base San Diego Monday as Expeditionary Strike Group Five left for its tour in the Pacific and Indian oceans.

He was wearing a black T-shirt that proclaimed "Like a Cabinet member" on the front and "I resign" on the back as he watched tugboats pull the Bonhomme Richard out of San Diego Bay.

Paredes, who compared his actions to that of recently resigned Secretary of State Colin Powell and other members of the president's cabinet, wanted to toss his military identification card into the bay but was told by officials not to so.

Military officials did not immediately comment on his actions. He could face a court-martial, a dishonorable discharge and possible time in a military jail.

Paredes said he has been told that he will face about up to 14 months in a military jail and a discharge for refusing to board the ship.

He said he hopes his protest might inspire other sailors, soldiers and Marines to refuse to take part in the war.

"I know other people are feeling the same way I am, and I'm hoping more people will stand up," he said. "They can't throw us all in jail."

Staff writer Louise Cannon contributed to this report.