Police say someone using a Burleson teacher's identity had improper chats with a 16-year-old student.
The English teacher at Centennial High School was accused last summer of having improper video chats with the teenager.
"Somebody else used his identity to commit this crime," Burleson police Cmdr. Chris Havens said. "That case was closed. He was cleared of that case."
Investigators have not stopped looking for the person who impersonated the teacher, but police now say he will not cooperate with their investigation.
"We have a lot of questions that aren't answered that we feel that he can help answer that will lead us to the suspect who really committed this crime," Havens said. "We'd like to talk to him to find out more information to help clarify and clear up some of the things that we found in the investigation they may lead us to the true suspect who committed this crime."
But the teacher told NBC 5 that he is fully cooperating with the police investigation and is eager to catch whoever impersonated him.
The teacher was also an assistant coach and was put on administrative leave after the incident. The Burleson Independent School District said he would not be offered another contract "in an abundance of caution."
The United Teachers Association said it is becoming more common for people to impersonate teachers online.
"It only takes one situation to ruin a teacher's career and, unfortunately, this teacher in Burleson is living this nightmare," said the UTEA's Steven Poole.
"We're seeing a lot of people creating false Twitter accounts, false social media accounts or logging into chat rooms to impersonate educators," he said. "We're seeing a lot of people trying to get back at teachers who are either failing students or students who are angry at teachers for whatever reason, and usually it's juveniles that we're seeing who are doing the impersonations."
The association advises teachers to periodically search online for any false accounts in their name.