A 23-year-old San Francisco man admitted to drinking at least 13 beers before getting into a car believed to have fatally struck another man on a street median last week, prosecutors said Thursday.

Juan Martinez is in custody on $1 million bail, but did not make his first court appearance Thursday, reportedly for health reasons, since being charged with vehicular manslaughter, hit-and-run, driving on a suspended license and driving while using a cellphone.

Police were called to Cesar Chavez Street and Potrero Avenue at 8:30 a.m. Saturday and found the victim. A driver had hit him before fleeing, police said.

Martinez was arrested about 3 p.m. that day, according to police. He told cops he had “13 to 14 beers” before getting into the car, which he reported stolen after the hit-and-run, prosecutor Susan Christian told a judge Thursday.

“But the investigation led to him and he made admissions,” Christian said.

A citizen came forward with information that led to Martinez’s arrest, District Attorney’s Office spokesman Omid Talai said. Martinez also has a federal immigration detainer, Christian said.

Outside court, Martinez’s attorney had no comment on the case.

Authorities have yet to release the victim’s name.

aburack@sfexaminer.com