LODI (AP) -- Five members of a Mexican family were killed Tuesday in a horrific traffic accident in the Central California city of Lodi, authorities said Wednesday.

All of the dead, including a pregnant woman and three children, were in the same extended cab pickup truck struck in the middle of a busy intersection during rush hour.

With the investigation ongoing, police Lt. Sierra Bruscia had few details to share about the wreck. He said investigators are looking into witness accounts that the driver of an SUV involved in the accident was speeding and talking on a cellphone moments before the accident. He did not know whether the victims wore seat belts.

"It's definitely a very traumatic incident," Bruscia said.

Police are considering the crash a criminal investigation, Bruscia said.

The names of the dead have not been released, but they are a man in his 30s, a woman who was seven months pregnant, also in her 30s, a 12-year-old boy, a 7-year-old boy and a 5-year-old girl. Brusia said a 9-year-old boy is in critical condition.

Mexican Consulate spokeswoman Mariana Carine Tyler told the Stockton Record that the family members killed are Mexican citizens.

All of the children attended Lodi schools.

Shortly after the accident Erin Andrews told KCRA-TV she was in traffic near the scene of the crash when she spotted the SUV swerving around cars at high speeds.

Another witness, Westley Ruyle, told the station the driver almost hit a few vehicles before the crash. He said he called 911 after seeing a "huge dust cloud."

"I approach and see this big old pile of mess, children laying out in the street, on the curb and bodies everywhere and vehicles totally messed up," Ruyle said.

Lodi, a city of more than 60,000 people, is located about 35 miles south of Sacramento.