Police are investigating two muggings in less than a half hour in Riverhead.

Police say the first victim was riding a bike on Robinson Parkway around 8 p.m. Monday when two men got out of a vehicle and attacked him. The attackers took off when a neighbor heard screaming.

Then at 8:30 p.m., a group of suspects allegedly got out of a vehicle a short distance away on Griffing Avenue and pistol whipped a man, stealing his bag and money.

The first victim has head injuries, and the second man has non-life threatening injuries.