In coordination with Washinton, and after the alleged Chinese surveillance balloon, Japan announced on Thursday that it is analyzing several unidentified aerial objects spotted over the past few years flying over the country.

"We are communicating with the United States but we decline to comment on diplomatic exchanges," chief government spokesperson Hirokazu Matsuno tells reporters Thursday.

"Having said that, we are analyzing objects observed above Japan in June 2020 and September 2021, including any links to the case in the United States," he added.

As pictures buzzed on social media by locals who viewed a mysterious balloon-like object flying over northern Japan back in June 2020, authorities expressed baffled behavior.

The posted media pictures showed a balloon object attached to crossed sticks with propellers.

As Japan’s meteorological agency rushed to explain that the floating device did not belong to it, the Japanese government ruled out any suggestions saying it may belong to a foreign government. However, recent events have raised some serious questions and prompted a re-evaluation.

With several other similar spottings with unknown affiliations in January 2022 over the sea west of Kyushu in southwestern Japan, Matsuno ensured that they will continue to make the utmost efforts to collect and analyze information with the cooperation of their ally, the US.

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With ongoing 24/7 airspace surveillance over the country by Japan’s Ministry of Defense, the Ministry refrained from confirming whether balloons like the one shot down by US forces had been observed over Japan.

"However, when we confirm a case of airspace invasion, we make announcements appropriately. We have never confirmed or made an announcement on any airspace violation by balloons," the Ministry said in response to a question by AFP.