The Barksdales escaped last month while being transported from NY to Arizona in connection with the murder of 72-year-old Frank Bligh in Phoenix.
The Barksdales, both suspects in the April murder of 72-year-old man in Tucson, were being transported from NY to Arizona when they escaped on August 26, authorities said.
'It was compelling enough that they felt the need to pull over, ' David Gonzales, the US marshal for Arizona, said of Susan's so-called medical emergency.
Both agencies plan to hold a joint news conference in Phoenix at 11 a.m. Thursday to provide further details about the couple's capture, Tucson's KOLD-TV reported.
The Navajo County, Arizona, sheriff's office said in a statement that the Barksdales were arrested without incident and that the sheriff's office assisted the marshals service in the capture.
Authorities believe they had help from Blane Barksdale's ties to white supremacist gangs along the way.
A statement from Tucson Police had said the Barksdales were being driven back to Arizona in the private security van when they allegedly overpowered and restrained their two guards, a man and a woman, during a stop in Utah. Investigators determined the fire was set intentionally and discovered that more than 100 firearms had been stolen from the residence.
The male and female guards weren't physically injured but the Barksdales used shoelaces to bind them and then put them in the back of the van with a third inmate, authorities say.
It took the guards more than two hours to free themselves. They don't think the couple made it to Mexico, KOLD says. Then they "abandoned the locked prison van with the three occupants inside".
The Marshals Service was offering rewards of $25,000 for information leading to the arrest of Blane and $10,000 for Susan.
The Barksdales have been charged with first-degree murder by Tucson police in the death of Frank Bligh, 72, who hasn't been seen since fire consumed his home April 16.
The Barksdales were arrested in upstate NY in May following a nationwide manhunt, officials said.