Authorities search for highway gunman

More than 70 investigators are working to catch the man responsible for firing at nearly two dozen passing vehicles in four counties over three days.

Tipsters say the gunman appears to be a man in his thirties with closely cropped hair.

Authorities have released this drawing of a possible suspect.

There have been three separate incidents reported in shiawassee county, though most involved cars are in wixom.

The Oakland County Sheriff says his forensic lab has determined that in seven of the cases, the bullets were fired from the same weapon.

So far, some 200 tips have come in to police.

No one has been hurt.