OAKLAND -- A 15-year-old girl killed Saturday night in an East Oakland shooting that also wounded two men was described by her school principal as a "brilliant" artist and a top student.

Samantha Alvarado was a ninth-grader at the Emiliano Zapata Street Academy, an alternative high school campus of 110 students at 417 29th St.

Principal Gina Hill said Monday that students at the close-knit school were "grief stricken" over her death. They expressed their feelings in a "talking circle" and also made altars in her memory.

Samantha was a passenger in a car when she was shot. The two men injured in the shooting, the 25-year-old driver of the car and a 27-year-old passenger, remained hospitalized Monday. Their names were not released. Police said Samantha and the men were Oakland residents and were friends.

Homicide investigators have not released a motive but said they have not ruled out the possibility that the shooting was gang-related.

The three were traveling in a car on 83rd Avenue, near A Street, about 10:25 p.m. Saturday when someone shot into the vehicle multiple times, police said.

The driver was able to back the car up before stopping against a fence in the 8200 block of A Street. Samantha was pronounced dead at the scene.

The driver was uncooperative when police tried to interview him at the hospital, where he was in stable condition. The other man was in critical condition.

Hill described Samantha as a "brilliant" budding artist.

"She was an extremely talented artist and was probably one of the strongest young ladies I ever met. I will always remember her strength and perseverance."

She said Samantha had recently won an art contest, and some of her work was to be displayed on billboards across the city.

"What I really want to emphasize is the positive," Hill said. (Samantha) attended school every day, she was passing all her classes and was one of our top students. She will be sorely missed."

Police and Crime Stoppers of Oakland are offering up to $20,000 in reward money for information leading to the arrest of the gunman. Anyone with information may call police at 510-238-3821 or Crime Stoppers at 510-777-8572.