Arnulfo Barron Cobos, about 50, is suspected of killing his common-law wife, Maria Teresa Herrera Diaz, 29, of 102 Dunhagan Court.

“The preliminary autopsy results make us very comfortable that it is a murder but we are not releasing the cause of death at this time,” said Maj. Tony Godwin of the Cary police.

“This is a case of domestic violence of the very worst kind.”

The department drew arrest warrants for felony murder on Cobos on Sunday, Godwin said.

Cobbs is alleged to have taken another roommate’s car, a silver 2004 Saturn L-300 bearing North Carolina license plate XWT-5469, from the residence between 4:15 and 5:15 a.m. Saturday.

Cobos is described as about 5 feet 6 inches to 5 feet 7 inches tall, weighing 200 pounds with a goatee.

Cobos is believed to have arrived in the United States from Mexico about eight months ago.

His whereabouts are unknown, Godwin said.

A female roommate found Diaz’s body Saturday and then called 911, Godwin said.

Godwin said he did not know how long Diaz had been dead when the body was found.

This murder is the third Cary police have investigated this year.

In February, Cary police arrested Harish Purushottamdas Patel, 60, of 1128 Woodway Bluff Circle in Cary for the murder of his estranged wife, Vanlata Patel, 57, whose charred remains were found on Jan. 16 just off Interstate 85 in Mecklenburg County, Va.

Cary police are still investigating the death of Nancy Cooper, who went missing on July 12, reportedly having left her home in the early morning for a jog. On July 15 Cary police confirmed that a body found at a construction site was Cooper’s. No one has been charged in her killing.

Without offering specifics, Godwin emphasized that the evidence points to the murder being the result of domestic violence and urged anyone in such a situation to seek help.

“We would like to encourage anyone, male or female, that is out there and in a challenging relationship to take the necessary steps to make themselves safe, to call someone, to call the police, to call a friend, to call Interact,” Godwin said. “But get some help.”