Nathaniel Huey Jr., a 31-year-old from Streamwood, Illinois, and a woman "with a relationship" to him were both called a "person of interest" before the woman was reported missing and in danger by her family on Tuesday night, Romeoville Deputy Chief Chris Burne told reporters.
A car linked to the man was spotted by a license plate reader in Catoosa, Oklahoma, just outside of Tulsa and about 650 miles from the crime scene, Burne said.
The vehicle was "unoccupied" and police "conducted surveillance of the area" before a "male and female entered the vehicle and began driving away," according to a statement by the Oklahoma State Bureau of Investigation.
Catoosa police attempted a traffic stop before the car sped away, continued on to Interstate 44 and then "struck the concrete barrier and came to a stop," the Oklahoma authorities said.
The car caught fire and “officers on scene heard two noises believed to be gun shots," Burne said.
Officers found a critically wounded woman inside the vehicle and the man fatally shot in the driver's seat, Burne added.
That man in the driver's seat is "believed to be Huey," according to a Romeoville police statement. The woman was taken to the hospital, where she died, Oklahoma state police said.
The fiery crash led to lanes of westbound Interstate 44, near Hard Rock Hotel & Casino Tulsa, to be temporarily shut down at about 11:30 a.m. CDT, NBC affiliate KJRH reported.
"Evidence has shown us a nexus between our suspect and the victims as well as possible motive,” Burne said.
The deputy chief declined to elaborate on that possible motive.
"Although Huey is identified as a suspect, this is still an active and evolving investigation," according to a police statement. "This portion of the incident is still unfolding."
Not long after the bodies were found, police dismissed any of the victims as the possible shooter and called the slayings a targeted attack that took place between 9 p.m. Saturday and 5 a.m. Sunday.
The victims were found Sunday night after a relative asked police for a “well-being check” because one of the victims did not show up for work, police said.