http://www.foxnews.com/story/0,2933,484326,00.html Transportation officials in Texas are scrambling to prevent hackers from changing messages on digital road signs after one sign in Austin was altered to read, "Zombies Ahead." Chris Lippincott, director of media relations for the Texas Department of Transportation, confirmed that a portable traffic sign at Lamar Boulevard and West 15th Street, near the University of Texas at Austin, was hacked into during the early hours of Jan. 19. "It was clever, kind of cute, but not what it was intended for," said Lippincott, who saw the sign during his morning commute. "Those signs are deployed for a reason — to improve traffic conditions, let folks know there's a road closure." "It's sort of amusing, but not at all helpful," he told FOXNews.com. • Click here to visit FOXNews.com's Cybersecurity Center. • Got tech questions? Ask our experts at FoxNews.com's Tech Q&A. Tampering with portable road signs is illegal and potentially dangerous to drivers. It is a misdemeanor in Texas, with penalties ranging from fines to potential jail time. Lippincott said the hacked sign — manufactured by IMAGO — is owned and operated by the city of Austin. Texas Department of Transportation signs have not been affected, he said. "It is always possible that it could occur, but we attempt to prevent hacking incidents," Lippincott wrote in an e-mail. He declined to comment on security measures to protect the state's signs from hackers. Austin Public Works spokeswoman Sara Hartley said the incident was not initially reported to police, but will be shortly. The sign was reverted back to its original message within hours, according to Hartley, who insisted the signs are tamper-resistant and equipped with external locks. "This sign was broken into, it was not just a 'walk up and change the sign' kind of thing," Hartley told FOXNews.com. "This is a new one for us, we've never had it happen before." Related Stories * Hackers Get Details of 4.5 Million Monster.com Members * Experts: New PC Virus No Reason to Panic * Microsoft: Obama's BlackBerry Is Security Risk * Data Breach May Have Exposed 100 Million Credit Cards * Mysterious New Computer Virus May Be 'Sleeper' Agent She said she did not know whether any other signs in the area had been altered. According to the blog i-hacked.com, some commercial road signs, including those manufactured by IMAGO's ADDCO division, can be easily altered because their instrument panels are frequently left unlocked and their default passwords are not changed. "Programming is as simple as scrolling down the menu selection," i-hacked.com reports. "Type whatever you want to display … In all likelihood, the crew will not have changed [the password]." I-hacked.com warns readers not to try to alter the signs, which cost roughly $15,000. ADDCO Chief Operating Officer Brian Nicholson told FOXNews.com that the company is sending out notices to customers on the potentially dangerous security flaw. "It's incumbent upon users to change the default password and secure the sign with a padlock," Nicholson said. "We're having our engineers review this information." In the meantime, if you're driving in Austin, you can rest assured: There are no zombies ahead.