A North Carolina man accused of killing his wife was arrested Sunday on an Arizona interstate, authorities said, adding they will take a closer look at the death of the man's first wife more than a decade ago.

Nash County, North Carolina, Sheriff Keith Stone said 57-year-old Rexford Lynn Keel Jr. was arrested during a traffic stop on the outskirts of Tucson, Arizona, by state troopers. Stone said a caller in Arizona tipped authorities that the suspect had been sighted on the interstate. Keel had a large amount of cash and a knife with him, Stone said, and the truck he was driving was searched.

The Nash County Sheriff's Office said it obtained an arrest warrant Friday accusing Keel of murder in his wife's death. The man's 38-year-old wife, Diana Alejandra Keel, had gone missing on March 9. Her body was found days later in another North Carolina county and Stone said it appears she had died of multiple stab wounds.

Investigators said Keel had fled in a pickup truck, launching a multiday manhunt.

Stone said Sunday that it appears the woman, a mother of two, had died of multiple stab wounds. She had a 10-year-old son with her husband, as well as an 18-year-old daughter, according to the sheriff.

"My heart goes out to the son, 10 years old, that's without a mother today ... and to the 18 year old daughter that's trying to further her education. What a traumatic experience. What a sad experience this is," he said.

The sheriff said the last person to report seeing her was a mail carrier who brought her a package shortly before she was reported missing.

Stone also said that investigators would be taking a closer look at the circumstances surrounding the death of Keel's first wife, which previously had been ruled accidental. Elizabeth Edwards Keel, 42, died at the couple's home on Jan. 1, 2006, according to the sheriff's office.

"We're going to go back and look at the information ... We're going to talk with the district attorney's office. But definitely it's something we need to be looking into," Stone told reporters Sunday when asked about Elizabeth Keel's death.

Matthew Lambert, who worked with Elizabeth Keel, told WRAL-TV that friends were surprised at the time that she had died in an apparent fall on some stairs. He described her as an "outdoorsy" person who liked to ride horses.

A recent news release from the Nash County sheriff's office said Elizabeth Keel's death was classified by a medical examiner at the time as accidental from "blunt trauma to the head" from falling and striking the front concrete steps of the family home.

Keel was listed as being held Sunday in the Pima County, Arizona, jail.