An NYPD officer involved in the controversial 1999 fatal police shooting of unarmed immigrant Amadou Diallo was promoted to sergeant on Thursday. NY1's Dean Meminger filed the following report.

There was applause from his some of his NYPD colleagues as Kenneth Boss was promoted Thursday from officer to sergeant.

For many others, though, it's nothing to cheer about.  Boss was one of four officers who shot at Amadou Diallo 41 times back in 1999, killing him.

City Councilwoman Vanessa Gibson said the promotion is a very sensitive issue.

"Because of circumstances that many may not understand around civil service law, I do think it is very hurtful," Gibson said. "Many people could perceive it as a slap in the face."

Diallo was in the entrance of his Wheeler Avenue building in the Bronx when he was gunned down by the four police officers from the now-disbanded street crime unit. They said they thought he was a rape suspect and was reaching for a gun. It turned out that Diallo wasn't wanted, and he only had his wallet and keys.

His mother, Kadiatou Diallo, said she can't believe Boss was promoted, and she's fought to get him fired.

"I said, 'I do not think he is fit to do the same job because he had killed before. The community do not trust him anymore," Kadiatou Diallo said.

The four officers were found not guilty at a trial that was held in Albany. Their defense successfully had the trial moved because there was too much publicity about the shooting in New York City.

Police unions say it's a tragic case, but they say Boss was no longer under any investigation and deserved to be promoted.

"He was acquitted in a court of law, and he took the test, did well. He was promoted. And I wish him and his family well and congratulations," said Michael Palladino, president of the Detectives' Endowment Association.

Two of the other officers became, firemen and another retired.

Amadou's mother Kadiatou Diallo says although she is troubled by this promotion, she's going to keep moving forward trying to bring police and communities together.

"Even though it is going to be 17 years, I am strong, I am empowered. I will continue to carry the mission of the Amadou Diallo Foundation," Kadiatou Diallo said.

She says that's helping others.