An Annapolis teen-ager died yesterday at Anne Arundel Medical Center after ingesting an unknown quantity of cocaine when county sheriff's deputies came to his apartment with an arrest warrant, authorities reported.

Deputies had arrived about 11 a.m. at the apartment in the 400 block of Captains Circle with a warrant for Maurice Richard McClain Jr., believed to be 18 years old, for violating probation.

The sheriff's office said McClain attempted to flee through a rear window, but spotted a deputy and retreated into his apartment. After deputies got inside, they saw him attempting to ingest suspected drugs and, in a struggle, tried to force him to spit it out. They recovered some of the substance, which later tested positive for cocaine, but apparently had been unable to keep him from swallowing some.

McClain was taken to the hospital for observation and treatment, and was cooperative before his condition worsened, the sheriff's office said, adding that he died at 3:12 p.m., shortly after his family arrived.

The sheriff's office said it would conduct an administrative review of the incident.