A truck loaded with vegetable oil collided head-on with a bus full of high school students in southeastern Brazil, killing 11 people, most of them teenagers, police said Tuesday.

The dead were seven students between the ages of 14 and 17, and four teachers. The bus and truck drivers and another 28 students were injured and rushed to nearby hospitals.

Police cited witnesses saying the truck veered into the oncoming lane and struck the bus head-on.

The accident occurred Monday night near the city of Ibitinga, about 22 miles from Borborema, the students' hometown.

The bus was among three returning from a field trip to Sao Paulo. The other two buses had already arrived in Borborema, when the accident occurred.