Forrest, 38, died on July 25 after being shot several times as he was being robbed at an Atlanta gas station.

"I believe in God and the justice system," his brother Alfonso Forrest told about 1,500 people at New Birth Missionary Baptist Church in Lithonia, just east of Atlanta. "We want justice fulfilled to the fullest within the law. It will happen."

Other boxing champs past and present on hand included Oscar De La Hoya, Evander Holyfield, Shane Mosley and Antonio Tarver.

Forrest was remembered during the service as a talented athlete who was a fighter for just causes outside of the ring.

He worked extensively with Destiny's Child group homes in Atlanta, which provide care for the mentally disabled.

"He's great, and what he did for the community was great," said Holyfield, who said he had known Forrest since he was 12.

Forrest was also among a number of people who lobbied the U.S. Congress for a posthumous pardon for Jack Johnson. The first black heavyweight champion was one of the few ever imprisoned under the Mann Act — he spent a year in jail from 1920-21 — which made it illegal to transport women across state lines for immoral purposes. The U.S. House and the Senate have both approved a resolution urging a pardon.

Police have not named any suspects in connection with the fatal shooting of Forrest.

Surveillance video near the scene of the homicide has been released to the public, and the case was featured on America's Most Wanted on Saturday. Police said they were encouraged by the tips that have come in as a result.

A native of Augusta, Ga., Forrest was a teammate with De La Hoya on the United States boxing squad at the 1992 Barcelona Olympics.

Forrest was the third boxing champion to die violently in July.

Former three-division champion Alexis Arguello, 57, died July 1 in Managua. Arguello, who had recently been elected mayor of the Nicaraguan capital, was reported to have died from a self-inflicted gunshot wound.