BANGKOK — Four days after the collision of the United States destroyer John S. McCain with an oil tanker east of Singapore, the search for 10 missing sailors continues to be painstakingly slow.

At least 20 divers from the United States Navy and the Marine Corps are working underwater with hydraulic cutters to try to enter crushed and flooded berthing compartments of the McCain where the remains of some sailors have been located.

The damage to the guided-missile destroyer is so extensive that divers must enter the ship through a gaping hole on its port side.

Kenneth Aaron Smith, 22, an electronics technician, third class, from New Jersey, was confirmed dead on Thursday; the Navy has also released the names of the nine who are listed as missing.