Complex sentence: The Lenox Avenue Gang was started sometime during the early 1900s by Gyp the Blood as an independent group under Jack Zelig's Eastman Gang mainly operating around 125th Street committing muggings, robberies, and murders.
Split into simpler sentences: The Lenox Avenue Gang was started sometime during the early 1900s by Gyp the Blood as an independent group under Jack Zelig's Eastman Gang. The gang mainly operated around 125th Street committing muggings, robberies, and murders.