WEBSTER, Texas -

Two separate groups of suspects have been violently robbing undocumented immigrants as they return home from work, Webster police said.

According to police, there have been at least eight robberies over the last four months. The victims are always men walking home late at night near an apartment complex on the 17700 block of El Camino Real Blvd.

Nearly everyone living at the apartment complex fits the same description:  Male day workers from Guatemala who are paid in cash and return home late from work, unaccompanied.

"Everyone is scared right now," one worker said.  "It's OK if (the robbers) take the money but (the workers) are getting hit in the head."

Police said guns have been used during attacks but usually the men are ambushed and beaten before being robbed of their day's pay.  One victim was beaten so badly, he had to be hospitalized.

Each day worker interviewed for this story refused to be identified citing the same reason many don't want to call police when they're attacked -- they're undocumented immigrants who believe it is them, not the suspects, who might get in trouble with authorities.

The suspects have been described as two different groups.  The first is described as two black males, in their 20's with medium builds and faces covered by bandanas.  The second group is described as two Hispanic males in their 20's with medium builds and their faces covered by t-shirts.

Crime Stoppers will pay up to $5,000 for any information that leads to the filing of felony charges or arrest of the suspects in this case. You can submit a tip several ways: Download the Houston Crime Stoppers in the Apple App Store, the Google Play Store and the Blackberry App World; call 713-222-TIPS (8477); text TIP610 plus your tip to CRIMES (274637), or visit Crime-Stoppers.org.

All tipsters remain anonymous.