The Iowa Division of Criminal Investigation is investigating the case. An autopsy on Riedmann's body is scheduled to be performed Friday in Des Moines.

Young said the incident was captured on a police squad car dash cam. The video will be released at an undisclosed time and date, he said.

The stop occurred at about 10:25 p.m. Wednesday on South Myrtle Street, near the Central Mart convenience store at 1203 Tri-View Ave.

The driver, Melinda Benoit, 39, of Sioux City, was pulled over because "there was an indication that there may be a wanted on the plate of that vehicle," Youngs said. Benoit was not arrested, but was cited for a traffic violation. The police chief said he did not know the relationship between Benoit and Riedmann.

State officials last month issued a warrant for Riedmann for a parole violation. Riedmann, who has a long criminal record dating back to 2001, was released from prison in June after serving a portion of sentences on felony charges in Woodbury and Polk counties, according to the the Iowa Department of Corrections website. In Woodbury, he was sentenced in March 2014 to 15 years on second-degree theft, habitual offender enhancement, according to court records.