4 injured in Sacramento apartment shooting

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A gun-wielding assailant opened fire at a Sacramento apartment with 16 people inside — including children — seriously injuring four people, police said Tuesday.

Calls came in about 9 p.m. Monday reporting shots fired and injured victims inside an apartment on the 4800 block of Myrtle Avenue, according to the Sacramento County Sheriff’s Department.

At the scene, deputies found three female victims — ages 39, 38 and 15 — and a 21-year-old male victim with gunshot wounds. Deputies gave medical aid to the victims before Sacramento Metro Fire took them to hospitals, authorities said.

The 39-year-old woman suffered a life-threatening gunshot wound in the head and was in critical condition Tuesday. The other three victims were in serious condition, the department said.

It’s not known whether there were multiple attackers, but police say it appears the gunshots were fired through the closed front door of the apartment.

Officials believe the culprit or culprits were known to the victims, and the victims had prior incidents with one suspect, said Sgt. Tony Turnbull, a sheriff’s spokesman. He would not disclose details of the previous confrontations.

Of the 16 family and friends gathered at the apartment, five were children who ranged in ages from 4 to 16, officials said.

Investigators continue to follow leads and were interviewing potential witnesses. No arrests have been made.

Anyone with information on the shooting can call the sheriff’s department at (916) 874-5115 or Crime Alert at (916) 443-4357. To remain anonymous, visit www.sacsheriff.com or call (916) 874-8477.

Jenna Lyons is a San Francisco Chronicle staff writer. Email: jlyons@sfchronicle.com Twitter: @JennaJourno