A 21-year-old woman was fatally shot inside a home across from Lowell High School in San Francisco, and police arrested the man they suspect of pulling the trigger, authorities said Friday.

The victim, identified by the city medical examiner as Valeria Villagomez, was shot shortly after 2 p.m. Thursday in a home on the corner of 26th Avenue and Eucalyptus Street, police said. Officers found her suffering from at least one gunshot wound and paramedics rushed her to San Francisco General Hospital, where she died.

Police arrested 20-year-old Jose Rodriguez on suspicion of killing Villagomez. Officials did not elaborate on a possible motive or the circumstances of the slaying, which they described as an “isolated incident.”

Lowell and nearby schools went on lockdown for 10 minutes while police responded to the scene. There was no threat to the schools or the students, officials said.

The killing marks the 32nd homicide of the year in San Francisco.

Violent crime in the city fell to a near-historic low in 2018, when there were 40 homicides through the end of October, according to the Police Department’s statistics.

Evan Sernoffsky is a San Francisco Chronicle staff writer. Email: esernoffsky@sfchronicle.com Twitter: @EvanSernoffsky