DALLAS (AP) — Electronic construction signs in the Dallas area appear to have been hacked, displaying messages calling Donald Trump a reptile and imploring early morning commuters to take a day off work.

The portable signs along Interstate 30 and elsewhere flashed messages early Tuesday including, "Donald Trump is a ... shape shifting lizard!" Another message read, "Bernie for president," referring to Democratic candidate Bernie Sanders.

Another sign said: "Work is canceled. Go back home."

The signs appear to be ones used by the Texas Department of Transportation.

TxDOT told Dallas-Fort Worth broadcaster KRLD that there's no humor in what the hackers did. The agency says the messages bumped warnings to motorists about nearby construction zones.

The Associated Press left a message for a TxDOT spokesman seeking comment.