MEXICO CITY (AP) " Prosecutors say a couple and their son were killed during an Easter week visit to a cave in central-east Mexico that is popular with tourists.

The Puebla State Attorney General's Office says in a statement Saturday that prosecutors believe robbery was the motive for the killings in the picturesque mountain region.

The statement did not reveal the names or nationalities of the victims who were killed in the Chivostoc cave in Cuetzalan municipality by unknown assailants who shot them and took their belongings. It also did not specify the date the crime occurred.

Also known as the devil's cave, the spot is the subject of many legends and is a popular tourist attraction in the mountainous zone of Puebla state near the border with the state of Veracruz.