COLLIN COUNTY (CBSDFW.COM) – Investigators with the Plano Police Department are working with several other law enforcement agencies trying to determine if a series of aggravated robberies are related.

Police say most all of the robbery victims are Hispanic and the crimes occurred during the early morning hours.

READ MORE: Opal Lee's Annual Walk Was Extra Special Saturday After Juneteenth Becomes Federal Holiday

(credit: Plano Police Department)

There are at least four suspects, all male, believed to be involved with the series of crimes. Police reports show the gunmen used pistols to commit the robberies and took cell phones, keys and wallets.

READ MORE: Fender Bender Leads To Shooting That Left 1 Dead, 1 Injured In Dallas, Police Say

(credit: Plano Police Department)

(credit: Plano Police Department)

During one of the crimes one suspect (pictured above) was wearing a light gray or white hooded sweatshirt. The suspects are known to drive a white 2001 Chevrolet Blazer four-door and a black 2002-2009 Chevrolet Trailblazer.

MORE NEWS: Police: Juvenile Girl Shot, Killed At Dallas Apartment

Photos of similar vehicles are also attached to this release. If you have been a victim of these suspects, please report this to your local law enforcement agency.