ALAMEDA -- Three juveniles were in custody and a number of search warrants executed throughout Oakland early Tuesday in a major break in the case of the Halloween evening slaying of a 15-year-old girl in an Alameda park.

The boys, ranging from ages 15 to 17, were detained today in raids on two Oakland residences, Alameda police Lt. Art Fuentes said. The teens are accused of shooting Ichinkhorloo Bayarsaikhan in the back shortly after 10 p.m. Wednesday in what police described as a robbery gone wrong.

The Alameda High School junior was pronounced dead a short time after at Highland Hospital in Oakland.

Police Tuesday found several weapons and ammunition at the raided residences and are hopeful they have recovered the gun used in the murder, Fuentes said.

"We have recovered several items of interest from the residences searched and are processing the items," he said.

The suspects are not related but are friends, according to Fuentes. Police are searching for at least two more suspects and "will continue to investigate until we find all those responsible," he said.

Bayarsaikhan was with about 10 of her friends when a group of about five or six male teenagers approached them and demanded their valuables.

"This was an attempted robbery and unfortunately we lost the life of a 15-year-old young lady at the prime of her life," Fuentes said.

The shooting marked Alameda's first homicide this year and has stunned the community and its law enforcement officials.

"This case has touched this police department, the city and the city government to the core," Fuentes said. "We try to keep our emotions in tact when we are investigating these types of cases. Both professionally and personally, this case has touched many, many of us."

The Alameda Police Department is continuing to ask for the public's help in identifying those responsible for the shooting. The Police Department has set up a hot line that is staffed by an officer 24 hours a day.

Anyone with information regarding the shooting is encouraged to contact the Police Department at (510) 337-8381.