Coast Guard crews continued the search Saturday for two teenage boys and their fishing boat after they went missing a day earlier off the coast of southern Florida, officials said.

Search and rescue vessels have covered more than 6,200-square nautical miles in an effort to find Austin Stephanos and Perry Cohen, both 14, after they were last seen around 1:30 p.m. Friday near the town of Jupiter, about 90 miles north of Miami.

The pair had bought $110 worth of fuel for their 19-foot white single-engine boat, the U.S. Coast Guard said.

Officials received a report that the boys had disappeared at about 5 p.m. after they didn't return to shore at the expected time.

The Coast Guard said Stephanos and Cohen were thought to be headed southeast, toward the Bahamas, but U.S. Coast Guard Petty Officer Mark Barney said the teens were not likely trying to make it all the way to the Bahamas. Their families told the Coast Guard that the young fishermen would not try to travel to the Bahamas alone and without permission.

Barney said the Coast Guard believes the boys don’t have many supplies or a communication device on board because they were not planning to be out on the water overnight. He told NBC News that crews had shifted their search area to Melbourne, about 100 miles up the coast from Jupiter, because they believe the boat is disabled and drifting north.