MEXICO CITY (AP) — A man suspected in the killings of a Mexican photojournalist and four women acknowledged being in the apartment where the slayings occurred, Mexico City’s top prosecutor said Thursday.

Prosecutor Rodolfo Rios told the Televisa network that the suspect was one of three men recorded by surveillance cameras as they left the apartment building Friday.

Rios declined to identify the man, but said the suspect previously served nearly 10 years in prison for rape and causing injuries.

Rios wouldn’t say whether the suspect had confessed to either the killings or the robbery that police say apparently was carried out at the apartment.

The victims included Ruben Espinosa, a photojournalist who fled the Gulf coast state of Veracruz because of intimidation. He was found shot in the head, his body bound and tortured. The attackers also killed his friend, activist Nadia Vera, and two of her roommates — a 19-year-old aspiring makeup artist and a woman from Colombia — as well as their 40-year-old housekeeper.

On Thursday, Colombia’s foreign ministry identified its citizen as Mile Virginia Martin. A statement said the identification was made through the victim’s fingerprints.

Authorities have not revealed the identities of the two other female victims.

Rios said investigators had not yet determined the motive in the killings, and that all lines of investigation remained open, including the possibility it could have been related to Espinosa’s work.