A freighter with 21 Haitians on board was intercepted by the Coast Guard (search) off the coast of Miami Beach (search) on Wednesday, hours after President Bush urged Haitians not to flee their homeland despite escalating violence.

Coast Guard Lt. Tony Russell said the approximately 200-foot ship had 28 people on board -- seven crew members and 21 Haitian nationals. It was stopped about seven miles offshore about 5:30 p.m. Immigration and Coast Guard officials boarded the ship two hours later.

Capt. James Maes, commander of the Coast Guard group in Miami, said officials were trying to determine whether the boat had been hijacked. He said three shotguns and a handgun were turned over to U.S. officials before they boarded the ship.

Russell would not confirm reports that the Haitians were seeking asylum. He said officials planned to interview the Haitians and the crew throughout the night while keeping them aboard the ship at sea.

"The situation is under control and peaceful, and we're working to keep it that way," said Russell, adding that there were no injuries.

The vessel's last port of call was Gonaives, Haiti (search), the nation's fourth-largest city and the site where rebels began the uprising Feb. 5.

Earlier Wednesday, Bush repeated the United States' oft-stated policy in recent days that it will turn back any Haitian refugees trying to reach American shores.

Rebels began an uprising Feb. 5 and control more than half of the Caribbean nation about 650 miles from Miami.

During Haiti's military dictatorship between 1991 and 1994, more than 65,000 Haitians were intercepted at sea by the Coast Guard, and most were sent back home. The flow of refugees eased after the United States sent troops to Haiti in 1994 and restored President Jean-Bertrande Aristide to power.