Laura DeLuca, a University of Colorado at Boulder instructor who was among the first group of Westerners invited into Sudan since the civil war began to abate, expressed concern over the recent death of the country's vice president in a helicopter crash July 30. John Garang, a former rebel leader, had played a key role in the Jan. 9 peace agreement that represented the end of a 21-year civil war fueled by historical, religious and resource conflict, she said. The helicopter crash was believed to have been caused by bad weather.