Graham, N.C. — A drug investigation by federal and Charlotte law enforcement expanded into a manhunt for six suspects in Alamance, Lee and Chatham counties Thursday.

Two suspects were arrested at a home at 9473 B Perry Road in Graham, near the Alamance-Chatham county line, Thursday afternoon, according to Alamance County Sheriff Terry S. Johnson.

The other suspects fled, sparking a ground and air search that lasted into the night, Johnson said. Two men were arrested during a traffic stop, but two more suspects remain at large. Their identities have not been released.

Authorities arrested Luis Maldonado Diaz, 42, of Charlotte, and Nicolas Hernandez Benitez, 39, of Charlottesville, Va., on three counts of trafficking cocaine and three counts of conspiracy to commit various drug crimes. They were placed in the Alamance County Jail under separate $450,000 secured bonds.

Luis Sanchez Riveria, 21, and Genoveva Jimenez Bautista, 24, both of unknown addresses, were charged with three counts of conspiracy to commit various drug-related crimes. They were placed in the Alamance County jail under separate $250,000 secured bonds.

Investigators said they seized 6 kilograms of cocaine, more than $75,000 in U.S. currency, an AK-47 assault rifle, 10 motor vehicles and various mechanical tools.

The search and investigation involved the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives, U.S. Marshal's Service, Federal Bureau of Investigation, U.S. Immigrations and Customs Enforcement, Charlotte-Mecklenburg area task force, the Lee, Chatham and Alamance county sheriffs' offices, State Highway Patrol, state Department of Correction and the Alamance County Fire Marshall.