About 200 students and several teachers at the exclusive Hackley School in Tarrytown have contracted a severe stomach virus, according to health officials.

The Westchester County Health Department says it is trying to figure out where the norovirus came from and how it spread.

Most of the students who were infected during this past week are from the middle school, although some are at the high school level.

School officials say the cause of the widespread illnesses does not seem to be from food poisoning but rather it is viral in nature. Officials say extensive cleaning is being done to sanitize common and eating areas to protect against any contagion.

Parents say the school has been sending continuous updates and instructions via e-mail.

According to the Centers for Disease Control and Prevention, the symptoms of a norovirus include nausea, vomiting, diarrhea. Some people suffer from chills, headaches and a low fever.

For a press conference with the county health commissioner on the virus that hit Hackley School, go to your digital cable box and select iO Extra, Channel 612.