A school headmistress was relieved of her chain, weighing nine sovereigns, by an unidentified biker in Pattukottai last night.

Krishnammal, of Maniyarkulam in Pattukottai and working as headmistress in a school in a neighbouring village, was walking to her house after getting off from the bus at head post office stop, when an unidentified person in a bike snatched her chain before speeding away.

Based on her complaint, Pattukottai police have registered a case and are investigating.