BALTIMORE (AP) — Federal authorities and police have raided two west Baltimore houses and arrested a man they say was the leader of a local gang.

Officials say they arrested 31-year-old Bryan Stewart on 10 counts of gun and drug charges after raiding two houses early Thursday morning. Twelve other people were detained, but Stewart, who police say is the leader of the Crips sect in Baltimore called the Rolling 60s, was the only person formally arrested.

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Baltimore City Police Commissioner Anthony Batts says the raids follow an uptick in violence in the Western District, where there have been 19 homicides this year.

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Gary Tuggle, assistant special agent in charge of the DEA Baltimore district office, says gangs were largely behind the looting of 17 pharmacies during the recent riots in the city.

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