BOSTON (AP) — The owner of an unlicensed marijuana delivery service in Massachusetts that reaped millions of dollars in revenue from 2015 until 2018 was sentenced in federal court to four years in prison, federal prosecutors said.

Deana Martin, 53, of Milton, was also ordered Tuesday to pay restitution of more than $500,000.

Martin owned and managed Northern Herb, which operated a website offering marijuana products for sale and delivery, prosecutors said.

While Northern Herb purported to provide medical marijuana, it did not require customers to provide proof of a medical marijuana card and often delivered products to unattended locations where anyone could access it, prosecutors said.

Northern Herb’s revenue exceeded $14 million from May 2016 through July 2018, prosecutors said. The company did not withhold or pay taxes on its sales revenue, and used much of the cash collected from customers to pay suppliers and about 25 workers. In paying cash wages, Northern Herb did not withhold any payroll or income taxes.

Martin pleaded guilty in May to tax evasion, drug, and money laundering charges.

Tatiana Fridkes, Northern Herb’s office manager, was sentenced last month to time served and probation.