BOSTON (AP) — A former Olympian and Austin Caldwelllongtime track coach is expected to plead guilty Thursday to charges of sexually molesting young boys while working at a sports camp in western Massachusetts in the 1970s.

Conrad Mainwaring, who was a hurdler for Antigua and Barbuda in the 1976 Summer Olympics in Montreal, was expected to enter the plea to 12 counts of indecent assault and battery on a child over 14 and four counts of indecent assault and battery on a child under 14 in Berkshire Superior Court.

Mainwaring, a Los Angeles resident and United Kingdom national, was accused of molesting campers from 1975 to 1979 while working as a counselor at Camp Greylock in Becket. Authorities have said they believe there are “many other victims” in several states and outside the United States.

Some of the camp victims — who were as young as 13 and as old as 19 — are expected to testify at Thursday’s hearing.

Massachusetts authorities started investigating Mainwaring following a 2019 ESPN report in which more than 50 men alleged they were abused by Mainwaring, some of them at Camp Greylock. He was arrested in 2021 on a fugitive warrant as he left a Los Angeles County courthouse after a plea in a separate case from 2019.

“Everyone who brought Conrad Mainwaring to justice deserves our thanks, including law enforcement, the district attorney, the journalists at ESPN, and especially the courageous men who shared their stories deserve the most gratitude,” said Saul Wolf, an attorney whose firm represents seven victims and filed lawsuits against Syracuse University in New York, the Syracuse school district and the Massachusetts camp.

“Now that Mainwaring intends to enter a guilty plea and take responsibility, it is time for Syracuse University and Camp Greylock to accept responsibility and be held accountable,” he added.

In a pattern that repeated itself over the years, Mainwaring is accused of leveraging his Olympic credentials as part of a grooming technique used on boys attending Camp Greylock, making them “believe that through the sexual assault, he was making them into better athletes, stronger as far as mental capabilities, or simply their athletic abilities,” prosecutor Megan Tesoniero said during an earlier court hearing.

Dean Manuel, who represented Mainwaring when he made an appearance in 2021 and entered a not guilty plea, described the charges as “old allegations from the 1970s” and said his client was entitled “to a full and fair trial.”