The lieutenant in command of the patrol was sentenced to 31 years and six months in prison, while seven other soldiers received a 28-year penalty, according to the state-run news agency Agencia Brasil.

The deaths of musician and security guard Evaldo dos Santos Rosa and a bystander, Luciano Macedo, sparked outrage and made a heavy impact at the time.

Santos Rosa, 51, was driving with his family in the Guadalupe neighborhood of northern Rio in a military-controlled zone when 82 shots rained down on his vehicle, according to the indictment. It was a Sunday afternoon and they were headed to a baby shower.

Santos Rosa died on the spot. His father-in-law was injured in the shooting, while his wife, seven-year-old son and a 13-year-old girl escaped unhurt.

Macedo was shot while trying to help the musician, and died days later.

"There is no defense for 82 shots. They were all fired with the same objective. Eighty-two shots is an execution," military prosecutor Luciano Gorilhas said during the trial.

An initial investigation found that the soldiers may have confused the family's car -- in which no firearms were found -- with that of supposed criminals.

Four other defendants were acquitted in the trial, which began Wednesday and lasted for about 15 hours, until early Thursday morning.

The defense announced they would appeal the sentences, local media reported. The convicted soldiers will not be placed in custody until all of their avenues for appeal are explored.

In statements published by news site G1, the deceased musician's widow, Luciana, said that the sentencing "brought peace to her soul."

"I know I won't get my husband back, but it wouldn't be fair to leave here without a positive outcome," she said.

The Brazilian military has taken part in numerous anti-criminal operations in Rio in recent years. From February to December 2018 they were in charge of security in the violence-plagued state.

A law passed in Brazil in 2017 determined that civilian deaths caused by military activity would be judged by the country's military court system.