An official says a Mexican tour bus carrying about 35 people has overturned along a southern Texas highway, killing at least two people and injuring an unknown number of others.

Texas Department of Public Safety spokesman Tom Vinger told The Associated Press the accident happened around 10 a.m. Tuesday on southbound Interstate 37, about 45 miles south of San Antonio.

Vinger says the bus came to rest on its side in the grassy median.

Vinger says the bus was traveling from San Antonio to Matamoros, Mexico.

Vinger says the injured were being transported to hospitals in San Antonio. He did not know if the driver was among the injured.