Japanese officials could revise how the country responds to flying objects that violate its airspace. The potential policy change comes after they announced a number of recent incursions.

Defense officials say unidentified flying objects have been spotted in Japanese airspace over the past four years. They are strongly suspected to have been Chinese spy balloons.

Japanese Prime Minister Kishida Fumio says Japan strongly urged the Chinese government through diplomatic channels to make sure that such incidents will not happen again.

Members of the main ruling Liberal Democratic Party say the Self-Defense Forces should be able to shoot down the balloons if they enter Japanese airspace.

Currently, they can only use weapons in self-defense or to evade imminent danger. Government officials want the SDF to be able to use weapons if it is deemed necessary to protect people including the safety of air traffic.

Meanwhile, Beijing is reacting sharply to Japan's announcements. Wang Wenbin, Chinese Foreign Ministry spokesperson, says the country strongly objects to Japan's slander and accusations against China without any firm evidence. Wang said Japan should avoid being influenced by what he called "an American publicity campaign".

The flying objects were spotted near a nuclear power plant and bases for the SDF and US military. A Japanese expert thinks China is trying to glean more about their activities.

Ohara Bonji, senior fellow of Sasakawa Peace Foundation, says when aircraft or ships go on missions, they communicate by radio and their sensor equipment releases radio waves.

Ohara says China probably wants to get intelligence from these signals, since that will make it easier to pick up signs of any shift away from routine operations.

The US military shot down a suspected Chinese spy balloon on February 4th. Beijing claims it was a "civilian airship" mainly used for weather research.

American officials say China has flown such balloons over more than 40 countries.