WHITE MARSH, Md. (AP) – Fire officials in Maryland said one Massachusetts student was taken to a trauma center in critical condition and 20 others were taken to area hospitals after they became ill on a charter bus traveling on Interstate 95.

Baltimore County Fire Battalion Chief Mark Ewers said Thursday night the bus pulled in at an Exxon station in White Marsh after several students complained of headaches and nausea and some vomited.

Officials aren’t yet sure what made the students sick, but Ewers says county commercial vehicle inspectors are looking at the bus.

Ewers says the students were traveling on the way to Laurel, Md. He said chaperones were trying to make arrangements to stay at hotels in the White Marsh area Thursday night.

AP-ES-03-22-07 2354EDT