MIAMI -- Investigators found blood and shell casings, but no gun, on a ghost ship at the center of a sea mystery, a prosecutor said Tuesday.

Defense attorneys argued that the charges that Kirby Logan Archer, 35, and 19-year-old Guillermo Zarabozo are being held for are not enough to not grant them bond and that there was no forensic evidence linking them to the killing of the captain and crew of the Joe Cool.

But a Miami judge decided to not grant bail for two men connected with the mysterious disappearance of four crew members from a fishing boat that the men hired for what was supposedly a pleasure trip to the Bahamas.

Archer, of Strawberry, Ark., is being held for fleeing prosecution for allegedly stealing more than $92,000 from a Wal-Mart in Arkansas where he was a manager. Zarabozo, of Hialeah, is charged with lying to federal agents about whether he was on the boat. Neither man has entered a plea to those charges.

Zarabozo told authorities that unknown pirates boarded the boat and fatally shot the crew members, but investigators have not verified his story or disclosed any evidence that would back it up.

On Tuesday, the assistant U.S. attorney made public more evidence that was found on the Joe Cool, including three shell casings from a 9 mm gun, although they did not find the gun. Two of the shell casings were found in the boat's cabin, where blood was also found, according to the attorney.

The discovery of a handcuff key aboard the boat was revealed last week by the FBI, but Tuesday investigators released information that they found a box that looked like it would contain handcuffs and a gun lock box that was empty in Zarabozo's bedroom.

The Joe Cool was discovered near the Cay Sal banks, about 100 miles south of its destination in the Bahamas on Sept. 23 after family members notified the Coast Guard around 4 p.m. after the vessel failed to return from a scheduled charter to Bimini. On Sept. 24, the two men were found about 12 miles from that site on the vessel's life raft.

Investigators said the pair had luggage and a backpack in the raft. The two also stayed in a South Florida hotel days before they chartered the boat, according to evidence presented on Tuesday.

The search for the four crew members was called off last week.

The five-day search encompassed 14,850 square miles between Daytona Beach, Fla., and Cay Sal Banks, Bahamas, according to Coast Guard officials. Still missing are Capt. Jake Branam; his wife, Kelly; crew member and half brother Scott Gamble; and Capt. Samuel Kairy.

The judge said the two were not only flight risks, but also called them dangerous to the community, Local 10's Glenna Milberg reported.

The judge said Tuesday that while the attorneys arguments in favor of the two men were valid, it was still not enough to grant them bond, so they are being held in pre-trial detention. Also, for the first time, it was publicly made clear that the case is a murder investigation and not a missing persons' investigation, said Milberg.