SAN FRANCISCO -- A 4-month-old boy left inside his father's car at the El Cerrito Plaza Bay Area Rapid Transit station has died.

BART spokesman Linton Johnson said the baby, whose name has not been released, was pronounced dead at Doctors Medical Center in San Pablo shortly after 6 p.m. Monday.

Johnson said the baby's distraught mother called police around 5:30 p.m. after discovering her son, who was unresponsive, in the car.

He said the boy's father normally leaves him with someone before parking at the BART station.

But he brought the boy to the station Monday.

Johnson said he did not know how long the boy was in the car.

He said the parents are being questioned by BART police.

Authorities are also not releasing the parents' names.