NASHVILLE, Tenn. -- A man with a long criminal record has been posing as a firefighter and visiting local schools, according to Nashville firefighters.

Video: Man Impersonates Firefighter, Visits Schools

Some Nashville firefighters said Gregory K. Pillow has been visiting schools and day cares and offering fire safety lessons for the past 18 years.

And, fire department officials said, no one has ever bothered to check his credentials.

"It is frustrating in that people tend to relax when they think they're in midst of firefighters or paramedics," said Nashville Fire Department spokesman Charles Shannon.

Firefighters recently received a memo from the deputy chief warning about Pillow and his impersonations.

In the memo, Chief William Curran talks about calls from people with day care centers asking specifically for Pillow to come and speak.

There's also a mention in the memo of a woman wanting to send a "thank you" note after Pillow spoke to a group in 2005.

According to officials, Pillow made contact with day care centers and schools offering his services. Real firefighters said that should have sent up a red flag since appearances are normally handled through the fire marshal's office.

"If somebody receives a call that there's a firefighter that's offered to come to your day care, that normally wouldn't be us. We wait for people to call, and we respond to that," Shannon said.

Pillow has a background of charges that includes domestic violence.

The memo about Pillow has been distributed to fire departments and various agencies including Bethlehem Centers of Nashville.

"Because we deal with precious lives, we always make sure people are who they say they are," said Bethlehem Centers of Nashville representative Kimberly James.

Nashville firefighters are working with Metro police in case. According to the memo, the fire department has issued security warnings to area schools.

Firefighters said that unfortunately, it's easy to get uniforms that look official at a number of stores.