DHAKA Schools have expelled some 5,400 teenage pupils on the first day of their final exams for cheating, newspaper reports said Friday. The annual secondary school certificate tests were also marred by violence in some of the 853 exam centers, including a vigilator who was stabbed by a pupil in northern Mymensingh outraged by his expulsion, AFP quoted the *** Bangladesh Observer *** as saying. Some 883,000 15 and 16-year-olds on Thursday began the month-long exams, with a further 151,800 students from the religious Madrasa schools also taking final tests.