Weeks after allegations came out from Firebaugh, investigators with Merced Police department say a 46-year-old man is claiming Harrison inappropriately touched him in the late 1980s.
"Doing the math, he was likely 16 years old when the incident occurred," said Lt. Jay Struble. "We're in the early stages, and trying to corroborate the statement given by the victim, and if Father Harrison was in the Merced area at the time."
The Diocese of Fresno placed Monsignor Harrison on paid administrative leave pending the investigation.
Records from the diocese show Harrison served at Our Lady of Mercy, and St. Patricks Catholic Church in Merced from 1987 to 1989.
Later, he served at St. Joseph in Firebaugh from 1992 to 1997.
A coordinator with the Survivors Network of those Abused by Priests (SNAP) says it's likely more alleged victims will come forward.
"For a second person to come forward and say the same thing, it makes it unlikely that it's a false allegation," said survivor support coordinator Melanie Sakoda. "We expect additional victims."
SNAP officials say it's common for victims to speak out on abuse several years after the incident, but because of a statute of limitations, the prosecution could be a challenge.
"It's likely that after 30 years there's no criminal prosecution, and it's also likely that there can't be any lawsuit," Sakoda said.
SNAP is also concerned about the delay in diocese officials reporting the accusations to police, calling for more transparency.
Harrison posted on his Facebook regarding the allegations, saying "I will vigorously defend my honor from these allegations and look forward to my good name being cleared."
Merced Police and the Diocese of Fresno asks any other alleged victims, or anybody who may have more information on the accusations, to come forward.