Filed at 3:30 p.m. ET

HARRISBURG, Pa. (AP) -- State epidemiologists will review health records to determine whether the deaths of six students from the same district are related, officials said.

The students, who were part of a 2,800-student East Pennsboro Area School District, have all died since December.

Medical examiners say the deaths are not related, and state air and water quality tests showed no remarkable levels of hazardous substances at the high school, which four of the dead students attended. The other two students attended public middle and elementary schools.

``I don't want to make this sound like we're doing this because we think there's a problem there,'' said Department of Health spokesman Richard McGarvey. ``But sometimes the best thing you can do is alleviate the concerns of the parents.''

The first three students to die, in December and January, all had life-threatening illnesses. The others, who died in the last three weeks, all had been apparently healthy.

The review, which will include individual records for the deceased students as well as records of all students visiting the nurses' offices, will begin sometime next week, McGarvey said.