Amid criticism from the family of a 16-year-old girl who was shot and killed in Detroit three years ago, the Wayne County Prosecutor's office says it's still awaiting more information from police on the case.

The victim's mother this week expressed dissatisfaction with the investigation - which has reportedly yielded a suspect and a weapon, but no charges - in an interview granted to the Detroit Free Press. The prosecutor's office on Tuesday told MLive an incomplete file on the case was submitted by police last year, and has yet to be updated .

Paige Stalker, a private school student from Grosse Pointe Farms, was struck in the head with gunfire when a man began firing upwards of 30 rounds from an assault rifle at at a car full of teens in east Detroit about 9:15 p.m. Dec. 22, 2014.

Two other teens in the vehicle were also injured, but survived.

The case spurred an outpouring of support in the form of candlelight vigils and marches, as well as the collection of reward moneys in excess of $160,000 for information leading to arrests in the case.

Unnamed police sources tell the Free Press the prime suspect, a convicted carjacker, was identified a year ago, and a portion of the murder weapon, an AK-47, has been retrieved.

However, there have been no charges in the case.

Wayne County Prosecutor Kym Worthy's spokeswoman, Assistant Prosecutor Maria Miller, says the Detroit police submitted their investigation a year and two months ago.

The July 15, 2016 submission was "more properly described as paperwork based upon information at the time," Miller said in an email to MLive, "not really a warrant request, and it was so deficient it was never logged into our system and was returned for further investigation."

She called the submitted paperwork "severely deficient and hurried work that should not have been presented."

It was returned to Detroit police on the same day it was received, Miller said.

According to the Free Press report, which included interviews with unnamed police sources and retired Deputy Police Chief Steven Dolunt, it's believed Paige was killed as a result of mistaken identity.

It's alleged the shooter opened fire on the vehicle Paige was riding in on the belief, rivals with whom he had a drug dealing dispute were inside, the Free Press reports.