ROCKLAND — A Thomaston man was sentenced to 20 years in prison for sexually assaulting four girls.

Robert J. Robinson, 65, pleaded guilty Jan. 12 in Knox County Unified Court to two counts of gross sexual assault, two counts of unlawful sexual contact and two counts of unlawful sexual touching.

After his release from prison, he will be on lifetime supervision and cannot have any contact with children.

Robinson was formerly employed with the Town of Thomaston as its animal control and traffic officer.

Robinson was initially arrested for sex crimes against two children on April 13, 2016 by Detective Justin Twitchell of the Knox County Sheriff’s Office following a complaint from a concerned parent and subsequent investigation. Robinson was charged with two counts each of gross sexual assault, Class A, unlawful sexual contact, Class B and unlawful sexual touching, Class D. His bail was set at $25,000, unsecured, according to the police affidavit.

More victims stepped forward after the arrest was publicized and Robinson was arrested again by Twitchell and then faced new charges of one count of unlawful sexual contact, Class B, and unlawful sexual touching, Class D. As before, the victims were under the age of 14.

Robinson’s new bail was set at $500 and he remained at the Knox County Jail until his sentencing hearing.

According to the court documents, one of the victims reported to Twitchell that Robinson was her frequent babysitter. She said he threatened to kill her if she told anyone about the assaults and she was scared.

Another victim thought she was about 4 years old when she was first assaulted by Robinson, court documents said.

The victims also reported that Robinson had given them money from time to time and bought them presents, such as toys and phone cards. When he was under investigation, Robinson dropped off a package with a gift of an electronic tablet at the door of one of the victim’s homes with a note saying “he was sorry he missed her,” according to the court documents.

Robinson was represented by attorney Philip S. Cohen of Waldoboro.

Reach Sarah Shepherd at news@penbaypilot.com