Japanese police on Sunday searched the Self-Defense Forces base where Kodai Murata is stationed, as well as his residence, after he was arrested for forcibly entering the Chinese embassy in Japan on Tuesday, according to Kyodo News.

Murata, 23, is a second lieutenant in the Japan Ground Self-Defense Force, stationed at Camp Ebino in Miyazaki Prefecture.

According to the Chinese embassy, Murata, claiming to be "an active-duty officer of the Japan Self-Defense Forces," forcibly broke into the embassy by climbing over a wall on Tuesday morning, threatening to kill Chinese diplomatic personnel.

Following this forcible intrusion, Japanese public figures have urged the government to take the incident more seriously, move beyond its current stance of expressing mere "regret," and formally apologize to China while conducting a thorough investigation to hold those responsible accountable.

Yujin Fuse, a veteran Japanese military journalist, said that responsibility for the incident lies entirely with the Japanese side and that Japan should acknowledge its fault and apologize to China, warning that refusing to do so may further aggravate the situation.

Seiko Mimaki, a professor at Japan's Doshisha University, noted that as a signatory to the Vienna Convention on Diplomatic Relations, Japan is obligated to prevent intrusions and damage to foreign diplomatic missions and should respond honestly to its failure to adequately protect the Chinese embassy in this case.

Ignoring this responsibility and prioritizing "not giving China grounds for criticism" would ultimately damage Japan's international credibility, she warned.

Yoichi Jomaru, a former journalist with Japan's Asahi Shimbun, questioned whether the Japanese government intends to close the matter by simply calling the incident "deeply regrettable."

"Logically speaking, at the very least, the defense minister or the foreign minister should come forward to apologize," he said. "Is the government deliberately allowing relations between the two countries to worsen further?"

The Chinese embassy has lodged solemn representations and a strong protest with the Japanese side, demanding that Japan provide a responsible explanation.

So far, the Japanese government has only expressed that the incident was "regrettable," without offering an apology or announcing specific accountability measures.