MIAMI BEACH, Fla. (AP) - The Coast Guard said it suspended its rescue operations at sunset Thursday after announcing earlier that afternoon that it had found four additional bodies in its search for dozens of migrants lost at sea off Florida.

Homeland Security Investigations officials have said they were actively investigating the case as a human smuggling operation.

Authorities have now found a total of five bodies, leaving 34 missing five days after the vessel capsized on the way to Florida from Bimini, a chain of islands in the Bahamas about 55 miles east of Miami.

Coast Guard Capt. Jo-Ann F. Burdian said earlier the decision to suspend the search was not an easy one.

“We have saturated the area over and over again,” she told a news conference. “We’ve had good visibility. ... We’ve overflown the vessel a number of times. ... It does mean we don’t think it’s likely that anyone else has survived.”

The Miami office of Homeland Security Investigations has launched an inquiry, saying the migrants’ journey was most certainly part of a human smuggling operation. Under federal law, a smuggler convicted of causing a death is eligible for execution.

“The goal of this investigation is to identify, arrest and prosecute any criminal or criminal organization that organized, facilitated or profited from this doomed venture,” said HSI Miami Special Agent in Charge Anthony Salisbury.