UTSUNOMIYA, Tochigi Pref. (Kyodo) The mystery of the raining tadpoles is back.

On Monday morning, a man working in a field in front of his house in Oyama, Tochigi Prefecture, reported that he found about 10 tadpoles, which he suspects fell from the sky.

Since last June, tadpoles falling from the sky have been reported in Ishikawa, Miyagi and Saitama prefectures. While some experts believe the tadpoles are dropped by birds, other lay the blame on tornadoes.

At around 8:30 a.m. Monday, Takao Nagano, 65, said he heard the sound of something dropping to the ground while he was planting melon seedlings in his field. He initially thought it was hail, but when he looked up the sky was clear, he said.

Then he found the tadpoles, each measuring about 2 cm, on the ground. Some were still moving, he said, noting they lying about 40 cm apart, almost in a straight line.

"Since the tadpoles had left a clear impression in the ground, they must have fallen from a great height," he said, adding that he didn't see any birds or airplanes flying over at the time.

A nearby waterworks worker said he also saw the polliwogs.