A two-year investigation of drug trafficking and violent crime in the Sedalia area has led to indictments against 37 people from western and central Missouri.

The U.S. Attorney's office in Kansas City says 28 defendants were picked up during a multi-agency sweep Thursday. Five others were already in custody, and four were still at large.

The defendants are accused in a half-dozen indictments with taking part in conspiracies that distributed more than $1 million worth of cocaine and crack cocaine. Several are also charged with illegally possessing firearms.

Most of the defendants are Sedalia residents. Several are from towns in neighboring Johnson County, Mo., and the rest are from Columbia, Blue Springs and Raytown.

Federal agents joined the Missouri Highway Patrol, several sheriffs' departments and police in Thursday's sweep.