(AP) — The latest man arrested by Omaha police in an effort to quash gang-related crime first got into legal trouble when he was 13 years old.

Omaha police say 31-year-old Michael Liggins was arrested Friday. A day earlier, local and federal authorities arrested four men as part of a nine-month investigation called “Operation Purple Haze” targeting gang-related activity, including gun and drug trafficking.

In all, 10 men have been arrested in the operation, all in their 20s and 30s.

Police say Liggins is a north Omaha gang leader who has been in and out of jail every year since 1999. In 2002, when he was 19, he was convicted of shooting and killing a friend who was trying to help him steal a car.