Inmate at Redwood City jail dies

REDWOOD CITY, Calif. - An inmate has died while in custody at a jail in Redwood City on Sunday, officials said. 

Jail staff were conducting routine checks on the inmates when a nurse noticed a 23-year-old man was having difficulty breathing shortly before 9 a.m. Redwood City Fire Department and AMR paramedics responded, but despite life-saving efforts, the man died. 

Authorities said the man was assigned to the East Housing Detox Unit.

It's unclear how the man died. 

Authorities from the San Mateo County Sheriff's Office, the District Attorney's Office, and the Coroner's Office are investigating the man's death.

Officials said care of the detox unit was "enhanced" last year after more people were arrested while under the influence of illegal narcotics.