The middle of Maha Navami night of Durga Puja (the ninth day (Mahanabami) is chosen for the worship of Goddess Mahamari (the Goddess of Plague/Epidemics). This is a highly secretive worship and is followed in certain particular temples in Bengal.
In the Raj Rajeshwari temple in Jamkuri village, Bankura,
the Mahamari Pat (scroll painting of the Goddess) is worshipped in the secluded
hours of deep Navami night. This worship of Goddess Mahamari began to seek relief
from the cholera epidemic.
At the Mrinmayee temple of the Malla kings in Bishnupur, the
Goddess associated with the Mules (Khachchar-bahini) or Goddess Mahamari is
worshipped in the middle of Navami night. It is said that the Malla king
introduced this ritual to protect his subjects from the plague.
The Goddess is worshipped on a scroll painting (pat). This pat
is kept hidden in the royal palace.
The scroll is brought from the palace in the dead of Navami
night. The chief royal priest sits with his back to the scroll and performs the
puja with his left hand.
During this time, no one else is allowed in the temple
except the royal family members and the priest.
Once the puja is over, the scroll is immediately returned to the secret chamber in the palace the same night.