CASA GRANDE, Ariz. (AP) – Four people were found shot to death along a highway Tuesday and four others were wounded in a dispute that apparently involved immigrant smugglers, officials said. Four suspects were later arrested in the desert.

Highway patrol officers first got calls about an accident along Interstate 10 outside Casa Grande, about 50 miles south of Phoenix, and later received calls about a shooting. When officers arrived, they found four people shot to death.

People in a van opened fire on a pickup and SUV believed to be transporting illegal immigrants, said Pinal County Sheriff Roger Vanderpool. The motive was unclear, but authorities suspect migrant smugglers, also known as “coyotes,” were responsible for the shootings.

Passengers in the pickup and SUV didn’t return fire, Vanderpool said. The driver and three men traveling in the pickup were killed. Two other people were injured.

Authorities said two people in the SUV, including a woman who was shot in the foot, were also wounded by gunfire.

Arizona is one of the busiest illegal entry points for those engaged in the lucrative business of immigrant smuggling.

“This phenomenon is not something new where we see a group being essentially ripped off by another group,” said Russell Ahr, spokesman for the Bureau of Immigration and Customs Enforcement.

Tuesday’s gunfire also caused a wreck involving three other vehicles that seriously injured one person.

AP-ES-11-04-03 1857EST

Only subscribers are eligible to post comments. Please subscribe or to participate in the conversation. Here’s why.

Use the form below to reset your password. When you've submitted your account email, we will send an email with a reset code.