In a case that caught national attention, the quest for answers in the murder of mother and fitness instructor Missy Bevers continues three years after her death.

Bevers was killed April 18, 2016 when she arrived at the Creekside Church in Midlothian to teach an early-morning fitness class.

Surveillance video from inside the church showed a person wearing makeshift tactical gear arrive before Bevers was killed. To this day, that person's identity remains a mystery and law enforcement have only been able to determine the person's approximate height -- at 5 feet 8 inches tall.

Another clue that may eventually lead investigators to a suspect has to do with the way the person in the video walked. Police noticed the person's unique gait, where his or her feet were turned outward, away from the body, more predominantly on the right foot. Police said it's possible the unique walk was caused by a temporary condition that may no longer be visible in the person in the video.

On Thursday, Midlothian police said they continue to actively investigate the murder case with the help of the FBI and Texas Rangers. Midlothian police said they've received more than 2,000 tips from all over the world about who might be the person behind the mask. Many tips, police said, involved people whom tipsters said had a similar walk to the person in the video.

None of the tips received have resulted in any named suspects and there’s no known motive for the murder.

Investigators are still interested in a vehicle captured on surveillance equipment in the parking lot of a nearby business in the early-morning hours before the murder was committed. The vehicle appears consistent with a 2010-2012 Nissan Altima, 2010-2012 Infinity G37 or similar vehicle. Police said the vehicle of interest is driving slowly around the closed business; the driver turns the lights off and on multiple times and then parks for a short time before exiting the parking lot.

In February 2018, Midlothian police assigned a new detective to the case, hoping a fresh set of eyes might turn up something that could break the case.

Bevers' family and friends were questioned in the case, they are not considered suspects.

A $50,000 reward has been offered for information that leads to an arrest and indictment.

Anyone with information in the case is asked to call a specific tip line at 972-775-7624. Tipsters can also share information anonymously by texting MIDL and the tip to 847411.