CIUDAD VICTORIA, Tamaulipas (CBSDFW.COM/AP) — An American family returning to the U.S. from Mexico came under attack just south of Texas Saturday, with armed gunmen killing a 13-year-old and wounding three others.

The attorney general’s office in the state of Tamaulipas said the child was a U.S. citizen and that the parents were permanent residents of the U.S. Their identities haven’t been released at this time.

The family was traveling in a Chevrolet SUV with Oklahoma state plates, returning from a holiday visit to relatives in the state of San Luis Potosi, according to CBS News.

The highway on which they were shot is considered high risk. It runs through an area that’s disputed by criminal groups, including the Gulf Cartel and Zetas. The road connects the city of Mier with Nueva Ciudad Guerrero, on the banks of the Rio Grande across the U.S.-Mexico border from Falcon Heights, Texas.

Saturday’s shooting came two months after nine American women and children were killed on a dirt road between the states of Chihuahua and Sonora in Mexico as they traveled to visit relatives.