Nineteen men, including three Americans, have pleaded guilty to federal drug smuggling charges stemming from the June 30 capture of a ship carrying 72 tons of high-grade Thai marijuana off the Washington coast.

Plea agreements with stipulated prison sentences ranging from six months to 10 years were accepted Friday by U.S. District Judge John C. Coughenour in return for the defendants' cooperation in prosecuting the alleged mastermind of a smuggling ring believed to have shipped hundreds of thousands of tons of marijuana to the West Coast since 1976.The alleged kingpin, Brian Peter Daniels, a U.S. citizen who has lived mostly in Bangkok the past 15 years, was arrested July 25 in Zurich, Switzerland, where he remains subject to extradition. Three other suspects are still at large.