Four newborn tiger cubs were killed due to 'suffocation' under the weight of mother tigress in Ranchi's Bhagwan Birsa Biological Park, a zoo official said on Tuesday.

The tigress Gauri gave birth to four cubs on May 10 but it turned over the newborn cubs and under the weight of the mother all four cubs died, the zoo veterinarian OP Sahu told PTI.

"The mother did not have child-caring experience. Gauri could not understand that she turned over her newborn cubs. The cubs died of suffocation under the weight of the mother by May 11," he said.