MIAMI -- A man accused of helping hijack a charter fishing boat named "Joe Cool" and murdering the four people aboard said he was tricked into the crime and that he lied to authorities because he was scared and confused.

Guillermo Zarabozo, 20, took the stand in his own defense Monday, a year to the day that the boat went missing after leaving Miami. He testified he didn't know 36-year-old Kirby Archer planned to hijack the boat and kill the crew.

Zarabozo said he thought the men were going to Bimini in the Bahamas to be bodyguards for high-ranking government officials, and that Archer, who claimed he had connections with U.S. intelligence agencies, said he could help Zarabozo work for the CIA. Zarabozo said he dreamed of a career in law enforcement or the military.

In fact, Archer was a robbery fugitive from Arkansas, and prosecutors said he was headed to Cuba to avoid investigators.

After they were at sea, Zarabozo said, he was in the bathroom when he heard shots and commotion. When he came out, he said he saw Archer holding the gun Zarabozo had brought aboard. Zarabozo said Archer ordered him at gunpoint to help throw the crewmembers' bodies overboard and clean up the blood.

Prosecutor Karen Gilbert asked Zarabozo why he wasn't suspicious that Archer didn't have ID or use credit cards or that he lied when he told the crew members the two were meeting their girlfriends in Bimini.

"At the time, I didn't think nothing of it," Zarabozo said. "It never came to a point where I had to question."

Zarabozo, a Cuban-American who came to Miami from Havana a decade ago, faces life in prison if convicted of four counts of first-degree murder, kidnapping, robbery and violations of maritime laws.

Archer has pleaded guilty to killing boat captain Jake Branam and his wife, Kelley, and crewmembers Scott Gamble and Samuel Kairy. He also faces life behind bars.

Prosecutors argue that Zarabozo was part of the plot for months, including bringing aboard the 9mm Lock handgun and extra ammunition and clips.

Gilbert asked Zarabozo why he didn't try to call for help or tell authorities the truth initially.

"I was afraid of what Archer was going to do," replied Zarabozo, so he went along with Archer's plan to say they were attacked by pirates. Zarabozo said they rehearsed the story when they were on a life raft, after the "Joe Cool" ran out of fuel. They were later rescued.

He said he lied because Archer had threatened to blame Zarabozo for the killings, since his gun was used and because he helped get rid of the bodies. Zarabozo later changed his story, telling authorities Archer was behind the crimes.

Gilbert pointed out discrepancies in Monday's testimony compared to what Zarabozo told authorities earlier this year. For example, interview transcripts show Zarabozo said he heard three or four shots, but then testified he couldn't remember how many. The transcripts said he was ordered to go upstairs while Archer dragged one of the bodies up, while on Monday, Zarabozo said he helped carry the body.

"I've been through so much, I can't remember everything perfectly," Zarabozo said.

Zarabozo told the jury he was "really sorry for what happened to those people."

Family members and friends of the victims said Zarabozo's story does not add up.

"He's fake," said Dawn Valentine, a friend of one of the victims. "He is out for nothing but to say, 'I didn't do it.' And, I mean, there was no way he didn't do it. I sit there and wonder when he's looking at the jury and biting his lip and pretending he's hurt and how he has been through so much."

"It's incredibly difficult," said Amy Gamble, a sister of one of the victims. "You have to sit there and listen to him and listen to what we know is not the truth. It's not the case. It's not what really happened."

The boat was found adrift far south of Bimini, about 18 miles from Cuban waters. Authorities found shell casings but not the murder weapon nor any of the bodies.