A founder of the shuttered classified advertising website Backpage was sentenced on Wednesday to five years in federal prison in connection with a sweeping case that led to the closing of the website and accusations against its executives that they promoted sex trafficking, prosecutors said.

Michael Lacey, 76, of Arizona, was convicted on a single count of international concealment money laundering in November after being charged in a 100-count indictment in 2018 with several other defendants who, prosecutors said, conspired to promote prostitution ads and launder earnings of more than $500 million made from the scheme between 2010 and 2018. The case was tried in the U.S. District Court for the District of Arizona.

In addition to the five-year prison sentence, Mr. Lacey was ordered Wednesday to pay a $3 million fine, prosecutors said.

The jury that convicted Mr. Lacey last year was deadlocked on 84 other charges against him, including several charges that he helped advertise prostitution on Backpage. The deadlock led U.S. District Judge Diane Humetewa to declare a mistrial on those counts. It was the second mistrial in the case. Mr. Lacey would later be acquitted of several of the counts, but could still face 30 of them, according to The Associated Press.

Two other executives, Scott Spear and John “Jed” Brunst, were convicted alongside Mr. Lacey on both money laundering and prostitution facilitation counts.

They were acquitted on some of those charges in April, but each received 10-year sentences Wednesday, according to a spokesman for the Justice Department, Joshua Stueve.