ORANGE COUNTY, Fla. -

Deputies in Orange County are trying to find Leonard Lewis, 47, who is a person of interest in the case of three people found murdered this week in a shed.

[RELATED: Cops: 1 of 3 found murdered called 911]

He's the ex-boyfriend of one of the victims. Local 6 has uncovered he also has a violent past.

Leonard Lewis

According to a 2007 arrest warrant, Lewis pleaded guilty to domestic battery in Osceola County and served more than six months in jail after violating his probation.

Lewis became violent after an ex-girlfriend tired of living a transient lifestyle and didn't want to marry him.

The charging affidavit said he forced her into a bathroom inside the home they shared and beat her. She tried to escape through the front door, but he grabbed her by the hair, ripping out a patch of it.

She later escaped to a neighbor's home where she screamed, "He's trying to kill me."

Lewis followed, beating her repeatedly and choking her. It was only after a neighbor called 911 that he stopped the brutal attack.

In this week's incident, deputies admit they didn't check the barn after one of the three victims called 911 around 9:40 to report a shooting.

Fifteen minutes later, someone else called 911 saying they also heard gunfire near the pond.

Sheriff Jerry L. Demings has ordered an internal review. He said he's not satisfied with the way his staff responded Monday night.