CHEROKEE COUNTY - Investigators are seeking the public's help after graffiti was found on the Killough Monument located on County Rd. 3431 -- about 7 miles northwest of Jacksonville.

Deputies were first alerted of the graffiti Saturday, but believe it may have been there since September 1.

On one side of the marker, vandals spray painted the letters 'C' and 'E' on either side of a heart.

The same thing was painted on another of the monument's four sides, along with "4ever" and "9.1.16" -- hence why deputies think the graffiti was left on September 1.

News of the vandalism left many Cherokee County residents upset.

"We don't approve," said Dr. Deborah Burkett, chair of the Cherokee County Historical Commission. "And we will not stand for this type of vandalism."

Burkett called the monument one of Cherokee County's most important historical sites.

"A massacre occurred at Killough Monument on October 5, 1838," she explained.

The massacre left 18 Texas pioneers dead or missing during a time of upheaval across the state.

"We're finding that it wasn't Native Americans [responsible] like first thought totally but it was a combination of renegades and others," said Burkett.

Nearly 200 years later, the monument stands in a rural part of Cherokee County. Bobby Abel, a lifelong resident, owns a deer lease nearby.

"The guys that own the lease come by and check occasionally... just see what going on," he said.

After one of the lease's owners saw the graffiti Friday, Abel posted a photo on Facebook.

"[I've seen] a lot of negative comments toward whoever would do this," he said. "And they shared it a lot so hopefully somebody will come forward."

Anyone with information on the case is asked to call the Cherokee County Sheriff's Office at 903-683-2271 or Cherokee County Crime Stoppers at 903-586-7867.

There is not a group or organization tasked with overseeing the monument, so Bobby and a group of volunteers will return to there Tuesday to remove the work of "C" and "E."

"We are blessed with interested people throughout East Texas who are going to work to see something is done," said Burkett.

A spokesperson for the Cherokee County Sheriff's Office said deputies plan to increase patrols around the monument until a suspect is arrested.