From the article:
A drug deal gone wrong in the parking lot of the Daly City BART station Sunday evening led to a 17-year-old boy getting shot in the back, police said.
The boy, who has not been identified, showed up at Seton Medical Center on Sullivan Avenue around 5:40 p.m. and claimed he'd been wounded by robbers who tried to steal his cell phone. But investigators later learned that he'd been shot in a car parked in the BART lot on the corner of John Daly Boulevard and De Long Street.
The shooting started after a drug transaction went bad, according to BART police. Police haven't reported any arrests.