A screengrab of Jalopnik's post about the media's coverage of edited sign messages. The photo looks similar to one that a Flickr user photographed in Bellevue.

Earlier this week, someone broke into the control box for a portable roadside safety sign near Bellevue and monkeyed with the messaged.

The state Department of Transportation and the State Patrol didn't find it funny.

The agencies are warning would-be vandals that tampering with a roadway safety sign is a crime.

"This is an issue that poses a potential danger to the traveling public and our crews," DOT Chief Engineer Jerry Lenzi said in a news release. "Drivers are in jeopardy because these signs notify them of potential hazards up ahead. For example they could encounter construction equipment or conditions and be seriously injured or killed. Our crews rely on these signs to direct traffic through the work zone to help keep them and the motoring public safe."

The news release doesn't specify what message was programmed into the sign, but according to one Web source it was "JALOPNIK RULES," a reference to a blog about cars. The blog also has photos of vandalized signs.

Vandalism of such portable signs made national news when someone in Texas changed a roadside sign to read "ZOMBIES AHEAD."

The messages on portable construction signs are individually programmed at the job site and are not connected to a central computer network, according to the DOT.

"These people risk potential felony charges," said State Patrol Capt. Jeff DeVere. "These signs convey important safety information and we do not consider this a harmless prank."