An Italian military jet crashed in flames into a suburban high school Thursday, killing at least 12 people and injuring 70, officials reported.

Students jumped out of windows of their two-story, red brick school to escape the smoke and flames, witnesses said. Others trapped on the top floor were rescued by firemen on ladders.Rescuers found one teenage girl uninjured under the plane's wing and continued to dig for bodies four hours after the midmorning crash. Bologna prosecutor Mario Forte said he expected the death toll to remain at 12.

Officials said all the dead were believed to be students. Many of the injured suffered serious burns. About 200 students, ages 14 to 18, were in school at the time.

Police said the pilot bailed out and the plane crashed minutes later into a classroom of the school, smashing a 12-foot-wide hole in the wall on the second floor.

"I saw this plane in flames coming down slowly, it seemed to level off and then it turned suddenly and crashed into the school," a witneses told state RAI television.

Students rushed in panic escape as flames and smoke swept through the building, witnesses said.

"The upper floor was full of flames and students who were immersed in the smoke were jumping out," a young woman said.

Another student was quoted by the Italian news agency ANSA as saying, "I was in class and saw through a window this low-flying plane coming at us and only had time to say: `This is crazy.' "

The plane, a Macchi 326 trainer, came down in Casalecchio di Reno, three miles outside of this city, and crashed into the Gaetano Salvemini technical high school.