Argentine authorities are holding a second man for questioning in the murders of two French women who were found shot to death last month in the northern Salta province.

Officials Tuesday said the man in custody may have sold a weapon that could have been used in the killings of 23-year-old Moumni Houria and 29-year-old Cassandra Bouvier. The women's bodies were found Friday along a hiking trail in a tourist area. Authorities say the women may have been kidnapped and sexually assaulted. A Salta official has said the two were last seen alive at an area hostel July 16.

On Monday, a man who rents horses in the area where the bodies were found, 43-year-old Francisco Ariel Tejada, was arrested, but later released for lack of evidence.

French and Argentine officials were closely monitoring the case in Salta.