In Northeast China’s Heilongjiang province, another three fiery metal objects have been spotted falling from the sky. The Saturday morning sightings come after five other unidentified falling objects were reported a day earlier.

All metal objects landed in Qiqihar, the province’s second largest city. According to witnesses, the first objects were seen in the sky at about 1 pm on Friday. Locals said they heard a noise and then saw a large oval-shaped ball of fire land in a vegetable garden.

Photos of the fallen object showed a metal sphere, half-covered by a layer with a jagged edge. One of the balls measured seventy centimeters in diameter and weighed around forty kilograms.

Residual nitrogen gas was found inside one, leading some to speculate that it was a nitrogen booster from an aircraft.