An Mi-17 V5 chopper of the Indian Air Force today crashed near Tawang in Arunachal Pradesh, killing five IAF crew members and two personnel of Indian Army. <br/><br/>A senior IAF official said the crash took place at around 6 am when the Helicopter was on a maintenance mission. A Court of Inquiry has been ordered to ascertain the cause of the accident. Meanwhile, rescue teams have reached the crash site in Tawang near the Indo-China border.