TOKYO (Reuters) -Japan’s Prime Minister Fumio Kishida, a day after escaping an apparent attack, vowed to ensure the safety of Group of Seven dignitaries visiting his country, beginning with tighter security for climate ministers gathering in Sapporo.

“My security has become even heavier this morning. It’s so tight I think it is going to be difficult to go out into the city,” Japan’s environment minister, Akihiro Nishimura, said at a the hotel in the northern Japanese city where he was hosting his G7 counterparts.

Bodyguards bundled Kishida to safety on Saturday after a man threw what appeared to be a smoke bomb at him during an election campaign stop at a fishing port in western Japan.

Heightened security “reflects an increasing challenge of being in politics these days,” said Canada’s minister of natural resources, Jonathan Wilkinson.

“Unfortunately I think that some of this has to do with the social media and some of the misinformation which spreads online,” Wilkinson told Reuters in Sapporo.

The suspect in Saturday’s incident, identified by police as 24 year-old Ryuji Kimura, was also carrying a knife when he was arrested, as well as a possible second explosive device he dropped at the scene after bystanders and police tackled him, Kyodo news agency reported.

No motive for the apparent attack, in which media said one police officer was slightly injured, has been announced.

Speaking to reporters, Kishida said Japan must not allow acts of violence that attack the foundation of democracy.

His bomb scare in Wakayama prefecture near Osaka was an eerie reminder of the assassination last July of former Prime Minister Shinzo Abe, who was shot with a homemade gun while campaigning for a parliamentary election.

Abe’s killing shocked Japan, where gun crimes are exceedingly rare, and prompted a review of security for politicians, who routinely mingle with the public.

Japanese politicians are campaigning for by-elections on April 23 for the lower house of parliament.

Chief Cabinet Secretary Hirokazu Matsuno said on Saturday that police have been instructed to boost security and the government would do what is necessary to ensure security when Kishida hosts other G7 leaders in May in his home town of Hiroshima.

“As politicians, we have to go out and campaign sometimes – it means we have to be exposed to the public,” Britain’s secretary of state for energy security, Grant Shapps, told Reuters in Sapporo.

“But I am quite sure that in the context of the G7 with our prime minister and other world leaders coming to Japan, we are perfectly safe,” Shapps said.

G7 foreign ministers gather on Sunday in the resort city of Karuizawa.

(Reporting by Mariko Katsumura, Tim Kelly, Katya Golubkova and Yuka Obayashi; Editing by Cynthia Osterman and William Mallard)

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