Police say 34-year-old Kevin Jones of Fairless Hills, a married father of two children, had a sexual relationship with a teenager he was coaching on the Levittown Bulldogs softball team.
Investigators are now trying to determine if there were other victims.
Falls Township Police Lieutenant Henry Ward explains, "He's literally had contact with hundreds of children over the past eight years."
"The concern at the police department at this time is he had so much access to potential victims," said Ward. "We want parents of these teams to speak to their children to see if there are any other victims out there."
Police say the relationship started in 2011 when the girl was 14, and continued until two weeks ago when the victim, now 15, confided in her sister, which led to their mother calling police.
Court documents say Jones told the victim: "I'll be your dad from now on, and I'll protect you like I'm your dad."
Lieutenant Ward tells Action News, "Mostly through various emails that were going back and forth through the victim and Mr. Jones - a total of 1,400 - it was obvious a sexual relationship had occurred between the two."
Police were planning to serve a search warrant on Jones' home last Friday morning around 7:00 a.m., but then just before 2:00 a.m. they were dispatched there for a fire. Jones' trailer burned to the ground and police say they weren't able to secure any evidence.
"We did learn checking various emails that the female victim told him they were coming. So we don't know if it was an accidental fire or intentional at this time," said Ward.
Police say Jones' daughter was a teammate of the victim.
A team mom who spoke to Action News said she was shocked over word of Jones' arrest.
"As a mom with a daughter on this team, it's a shame and shocking that someone we know would do something violating to a child," said Kelly Roth.
Roth also helped coach the team. She says the team checked out all of the coaches before the season, including background checks.
"We would never, ever have thought that this was going on behind closed doors. Never, ever," she said.
Team members say Jones left about a year ago after some disagreements with the coaching staff, which were unrelated to these allegations.
Jones was taken to Bucks County prison Monday night, where he is being held on $2 million bail.