Law enforcement officials say Holder got into a dispute with Hussle before the shooting, alleging that Holder shot Hussle and two other men before returning back to the scene and firing several more shots at Hussle before ultimately kicking him and taking off.
Moore, speaking at a news conference that was being broadcast live, said he was confident that Holder was watching.
"The community is the one that is helping us solve this case", Moore said.
The police chief and the president of the city's Police Commission had been scheduled to meet with Hussle on Monday to discuss the relationship between the police force and the inner city.
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Moore said the stampede began when one person displayed a gun, and a second person struggled to disarm the person.
Two witnesses told CBS Los Angeles that a fight broke out between two groups, but there isn't a clear link between the fight and the stampede. Fire officials said two were critically injured, one of whom was stabbed and another of whom was hit by a vehicle. - He is the only suspect who has been publicly identified by the LAPD in the shooting death of Nipsey.
Hussle, 33, whose real name was Ermias Asghedom, was shot multiple times Sunday afternoon and rushed to a hospital, where he was pronounced dead.
His debut studio album, Victory Lap was nominated for Best Rap Album at this year's Grammy Awards.