Officials are on the lookout for thieves who are targeting expensive stop signs in the Waterloo area.
The stop signs and advance warning signs are equipped with light-emitting diode bulbs and powered with small solar panels.
They cost about $1,500 each. They were put a year ago to make them more visible to drivers.
One of the signs at a dangerous intersection near the John Deere Tractor Works was stolen last week. It was found three days later
in a ditch. The sign was put back up.
Thieves then stole that sign and two others either between late Sunday or early Monday.
Regular stop signs are been installed while officials search for the missing ones.