Police in Killeen have increased their presence around the city's Walmart locations after receiving a report about a threat from a possible gunman.

According to KPD Spokeswoman Carroll Smith, police were alerted to the possibility of a threat Tuesday and sent a confidential bulletin to local law enforcement advising them to be on alert. Smith said the department did not make the information public due to concerns that it might cause undue alarm to citizens.

Smith said police were notified by a citizen who received a text from a relative stating he might "one day" carry out a shooting at one of three Killeen Walmart locations. After interviewing the relative, police increased security at the stores while detectives worked to assess the validity of the threat.

In a release issued Thursday morning, Smith said detectives determined that the person who made the threats "may not have been able to immediately carry them out, and they may have been made out of frustration". The bulletin attributes the man's frustration to a missed custody hearing.

Smith said detectives are still trying to locate the person believed to have made the threats and believe he is aware of the investigation.