PORT ARTHUR, Texas — Four people believed to be gang members were arrested in Port Arthur Monday night. 

The arrests happened when a Port Arthur Police Officer did a traffic stop just before 8 p.m. Nov. 11 in the 3800 block of Gulfway Drive. 

"This minor traffic violation initiated an investigation that ultimately resulted in all four occupants of the vehicle going to jail," Port Arthur Police posted on the department's Facebook page. 

The driver was arrested for defective equipment, but the other three people in the car were arrested on gun-related charges, police said. One of these charged may be federal. 

"It is believed that all four suspects are gang members," the post said. 

Officers found two handguns and ski masks hidden in the car, and Port Arthur Police said they believe the officer prevented a violent crime just by doing a traffic stop. 

This was a team effort, police said. 

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