"We are worried about our politicians. During campaigning they become more visible, they take part in debates, and generate more attention," said Benedicte Bjørnland, head of Norwegian security police (Politiets sikkerhetstjeneste - PST).
She added that increased visibility could trigger people who have anti-authoritarian tendencies, but did not say that her agency had identified any direct threat of political attacks.
"We try to be ahead of the game so nothing happens, but you can't rule it out," Bjørnland.
Several ministers were assigned PST bodyguards after the terror attacks on July 22nd, 2011.
The Bergens Tidende newspaper reported that in June, Erna Solberg, the leader of opposition party Høyre, became the only party leader apart from the prime minister, who leads the ruling Labour Party (Arbeiderpartiet), to get a bodyguard.