A fugitive couple being sought in the kidnapping of three children whose mother was found dead off a remote Gorman-area road were arrested in Colorado Thursday, authorities said.

The Los Angeles County Sheriff’s Department announced Wednesday that investigators were seeking Joshua Robertson, 27, and Brittany Humphrey, 22, in connection with the death of Kimberly Harvill, whose body was discovered Aug. 14.

The couple, from the Fresno area, were together at a motel in the Lebec area with Harvill and her children in the days before the victim’s body was found by a passing motorist, authorities said.

Harvill was believed to have been dead less than 24 hours when she was found. She was identified after sketches of her face and her tattoos were released Aug. 18.

The couple took Harvill’s three children out of state, and then left them with a good Samaritan at a motel in Grants, New Mexico. That good Samaritan became suspicious and called local police; the children were found safe Wednesday but the search for the couple continued.

Another, unrelated 1 1/2-year-old girl was believed to have remained with Robertson and Humphrey. She was considered at risk and missing, sheriff’s homicide Lt. Joe Mendoza said Wednesday.

That child, identified Thursday as Madisyn Harper, was safe, unharmed and in protective custody, a sheriff’s deputy told KTLA.

Harper was in Robertson’s care while her mother was in prison in California, Mendoza said.

Humphrey is Harvill’s sister. Humphrey and Robertson, who has a criminal record and is on parole, are girlfriend and boyfriend, Mendoza said.

The couple were arrested in Pueblo, which is about 100 miles south of Denver. Arrests warrants had been issued for them in the children’s kidnapping, and they are considered “persons of interest” in Harvill’s homicide.

Police in Pueblo were conducting an unrelated investigation at a local motel when they found Humphrey with Harper. They were in the green Ford Expedition that the Sheriff’s Department had alerted the public about, Mendoza told KTLA Thursday evening.

Robertson was found two blocks away. Both were taken into custody about noon without incident.

The process of having them extradited to California was underway, Mendoza said.

Authorities initially said Harvill’s three children — Joslynn Watkins, 2; Brayden Watkins, 3; and Rylee Watkins, 5 — were found in Albuquerque. They were actually found in Grants, which is about 80 miles west of Albuquerque, Mendoza said Thursday.