Tetsuya Shiroo, 59, a senior member of a local gang affiliated with Japan's largest crime syndicate, the Yamaguchi Gumi, was arrested and a revolver he had with him was also confiscated.
|Ito was campaigning to win a |
fourth term as mayor [AFP]
The motive for the shooting remained unclear, but public broadcaster NHK said Shiroo was upset at the city's handling of a traffic accident four years ago in which his car was damaged as it passed a public works construction site.
After an emergency operation that lasted for around four hours, Ito was kept alive for some time by an artificial heart and lungs but died at 02:28 am due to loss of blood, a police spokesman said.
Doctors had told a news conference that two bullets had reached his heart.
TV footage earlier showed the mayor lying face down on a sidewalk with his eyes closed as paramedics performed cardiopulmonary resuscitation after he was gunned down.
Japan has very strict gun control laws and firearms are mostly located in the hands of "yakuza" gangsters or hunters.
Nagasaki, on the southernmost main island of Kyushu and around 980km southwest of Tokyo, was the second city to suffer an atomic bombing by the United States on August 9, 1945.