MILWAUKEE — Eighteen people have been arrested in the Milwaukee area in a nationwide drug distribution and money-laundering operation.

Law enforcement officials say about $1.3 million in cash was seized along with large amounts of cocaine, heroin, methamphetamine and marijuana.

U.S. Attorney Gregory Haanstad in Milwaukee says the drug operation stretched from Mexico to California to the Midwest. Authorities say the operators concealed the drugs in hidden compartments in vehicles and then loaded the vehicles onto commercial automobile carriers and transported them to the Midwest.

All the defendants live in the Milwaukee area and are charged with possessing and distributing controlled substances and conspiracy.