Milwaukee police say a recent shooting that left four people dead was the result of a turf war between rival gangs.

Police chief Edward Flynn said yesterday the two male victims were members of a group known as the Murda Mobb. That's a drug-running group he says moved from Chicago to Milwaukee in the 1990s.

He says multiple gunmen fired into the crowd of at least 100 early Friday morning, targeting the two men in retaliation for a previous offense.

Two women who were also killed are believed to have been innocent bystanders. Two others were injured.

Flynn says the Murda Mobb was responsible for at least 20 Milwaukee murders in the last 10 years. He says police will step up patrols and take back the streets.

Milwaukee Mayor Tom Barrett says community members also need to step forward -- even if that means turning in a family member.

No arrests have been made.

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