As Japan beefs up security for the Group of Seven summit in May, separate attacks on its present and former prime ministers within a year have highlighted shortcomings in the nation's ability to protect high-profile figures like those set to gather in Hiroshima.
Following the latest attack by a man who targeted Prime Minister Fumio Kishida by throwing an explosive device at him as he campaigned in April, top government spokesman Hirokazu Matsuno vowed to take all possible measures to ensure the safety of those attending the international event.
The incident took place despite increased security after a man shot and killed former Prime Minister Shinzo Abe last July when he was giving a stump speech in the city of Nara ahead of a national election.