The mother of a 17-year-old boy fatally shot two weeks ago in Brooklyn Park is begging for anybody with information about who fired the deadly shots to come forward.

Alvera Voss made the plea Thursday during a news conference where police said two 17-year-olds now in custody allegedly bought gun parts online and used them to assemble two firearms connected to the killing of Syoka Siko on Nov. 18.

"We would like closure and justice," Voss said. "Help figure out who killed my son. State what you know. You know the truth will set you free."

Investigators have been trying to piece together what happenedthe night Siko died. What they said they know is that four 17-year-old boys — described by Brooklyn Park Police Chief Mark Bruley as "associates" or "friends" — were in a vehicle near an apartment building on Regent Avenue. About 8:30 p.m., three to four shots were fired inside the vehicle, Bruley said.

One of the passengers was trying to shoot at somebody or something outside the vehicle, but the rounds struck Siko and another teen, Bruley said.

There was no evidence that anybody had shot toward the vehicle, the chief said.

He said the four teens drove from the scene down Regent Avenue and onto Brooklyn Boulevard. At some point, Bruley said, they stopped to hide the guns before proceeding to Interstate 94 near 53rd Avenue in north Minneapolis. They then called 911, and the State Patrol arrived.

Siko died at a hospital. A second teen was treated for a nonlife-threatening gunshot wound, Bruley said.

The two other 17-year-olds in the vehicle have been arrested and were being held at the Hennepin County Juvenile Detention Center on suspicion of aiding and abetting murder. One is believed to have been the shooter, Bruley said.

The chief said the two have not been cooperative. He said police still want to talk to another teen.

The case is troubling for police because it shows how easily anybody, even teenagers, can buy gun parts and assemble a "ghost gun" — a firearm that has no serial number or registration.

Brooklyn Park police Inspector Elliott Faust said evidence found at one of the teens' homes revealed they used fake names to buy the gun parts from multiple manufacturers and had them delivered by mail. The purchases were made within the past month, he said.

Brooklyn Park police this year have recovered 119 guns, including 26 ghost guns.

"It's a real concern about how easy it is to obtain guns," Faust said. "They can order a kit to assemble and create working firearms, even 17-year-olds. It is almost like playing Legos."

Friends and family members organized a community conversation about youth guns, violence, gangs and drugs Thursday night at Ebenezer Community Church.

Siko was an honor roll student and played basketball last year on the junior varsity team at Park Center High School. He was also on the postseason roster when the Pirates won the Class 4A state championship. He had transferred to Andover High School this year.

"His death is tragic and [it is] extremely hard to imagine the pain his loved ones are going through," said a fundraising site set up on behalf of Siko's family.