Indore, June 4 -- A month after an unknown animal attacked 18 villagers sleeping outdoors in Limbai village of Barwani district, six have died. Authorities still don't know what bit them - or why.

The latest victim, 50-year-old Chain Singh, died on Sunday at MY Hospital, Indore. Hours earlier, 40-year-old Sunil Nigwal died after being sent home from the same hospital.

Most victims came from tribal villages like Limbai and Solyapura. They were attacked on the night of 5 May while sleeping outside to escape the heat. All had clear bite wounds - some on their faces.

They all got anti-rabies vaccines quickly, but none showed normal signs of rabies. Doctors say the symptoms are strange. The bite marks differ in size and pattern.

Officials re...