Massachusetts post offices confiscated a record number of marijuana bundles in 2018 — the same year recreational pot shops opened up in the state, CBS Boston reported. While it is legal to buy and sell marijuana in Massachusetts, it is not legal to mail it.

Last year, local postal inspectors confiscated 434 marijuana packages through the end of November. That is more than triple the rate since its legalization in the state in 2016.

"It's still illegal under the Federal Controlled Substances Act. People have to be aware of that," Stephen Doherty, a U.S. Postal Service spokesperson, told CBS Boston. Doherty said postal inspectors have no plans to slow down or cease these types of confiscations.

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The Federal Drug Enforcement Agency (DEA) still supports its policy of intercepting packages containing pot. "It's against federal law, and our job is to just follow that law," said Special Agent Jon DeLena. "We're always focusing on the largest scale drug trafficking organizations that we can identify."

While several states have legalized both medical and recreational marijuana usage, the federal government still classifies cannabis as a Schedule I drug — a category that also includes heroin, LSD and ecstasy. According to the United States Drug Enforcement Agency, cannabis has "no currently accepted medical use and a high potential for abuse." It is considered more dangerous than drugs like cocaine, methamphetamine and OxyContin.

At least 55 of the confiscated packages contained less than one ounce of marijuana, records show. One weighed less than a penny. Only two percent of packages seized contained opioids.

"Here in New England, sadly, we know that fentanyl is readily available," DeLena explained. "So we don't have a lot of cases where people are going online and ordering packages through the mail."

Sending or receiving marijuana through the mail is a felony that can lead to up to five years in prison. In cases involving larger quantities or second offenses, the punishment can be even more severe.