U.S. District Court Judge Helen Gillmor sentenced a Hawaii island man, found guilty in his second drug trafficking case, to 20 years in a federal prison Monday, prosecutors said.

A jury convicted Francis S.K. Ogata, 34, of possession with intent to distribute about 145 grams of methamphetamine in January.

The U.S. Attorney’s Office said U.S. postal inspectors became suspicious about a package mailed from Las Vegas to Hilo and found it contained methamphetamine. Ogata picked up the package and was followed by law enforcement officers back to his home, where he was arrested on Feb. 3, 2012, prosecutors said.

Because Ogata had been convicted in 2005 of another drug trafficking offense, the judge was required to sentence him to at least 20 years in prison, the U.S. Attorney said.