A crew distracted by a soccer game on TV? A radar system left off? Was the fog really that thick?

As night fell Thursday and with it nearly all hope to find alive any of the 139 people missing from the ferry Moby Prince, the question changed from "Can anyone have survived?" to "Why did they die?"Human error probably caused the ferry to crash into an oil tanker and explode into flames Wednesday night, a government minister said Thursday as he announced an inquest into the accident.

By the time rescue efforts were halted at dusk on Thursday, only one survivor was rescued from the ferry and 40 bodies had been recovered. The tanker crew survived.

Officials could only speculate on exactly what led the 6,187-ton Moby Prince to plow into the tanker anchored just beyond this busy port on Italy's northwest coast.

Some pointed to the testimony of the only survivor from the ferry that he and other crew members were glued to a televised soccer game. Others said there had been a thick fog - in the harbor area.

According to a member of the Leghorn port control room, which monitors ship traffic in the harbor, the Moby Prince didn't even send out a distress signal.

The collision occurred as the Moby Prince ferry was traveling, about 21/2 miles off Leghorn, toward Olbia, Sardinia.