Canadian Prime Minister Justin Trudeau says he plans to continue election campaigning as normal, a day after wearing a bulletproof vest to a political event.
Police sources quoted by Canadian media said there had been a security threat, but details were not made public.
Senior political figures in Canada rarely need high levels of protection.
Mr Trudeau’s rival candidates have condemned any threats to political figures.
On Saturday, Mr Trudeau appeared 90 minutes late at a campaign rally in Mississauga, Ontario, and body armour was visible beneath his shirt and jacket.
He was also surrounded by a uniformed security detail wearing backpacks. The backpacks held firearms, police sources quoted by Canadian broadcaster CBC said. Another officer was carrying a ballistic shield, CBC added.
Mr Trudeau made a speech surrounded by officers and then mixed with the audience before leaving. His wife, Sophie Gregoire-Trudeau, had been expected to introduce him but did not appear, local media reported.
On Sunday, Mr Trudeau appeared at another campaign event wearing just shirtsleeves without any protection underneath.
“This will not change at all how I campaign,” he said during the event in York.
Asked about any threats against him, he declined to give details saying that his first concern had been for his family and for those at the rally.
“I took advice from the RCMP (Royal Canadian Mounted Police), worked with them,” he added.
Andrew Scheer, leader of Canada’s Conservative Party and Mr Trudeau’s main election rival, took to Twitter saying that “threats against political leaders have absolutely no place in our democracy”.
Also on Twitter, leader of the New Democratic Party (NPD) Jagmeet Singh called the threats “troubling”.
It is not the first time in recent months that normally relaxed Canadian politicians have needed increased security.
In September, environment minister Catherine McKenna was assigned a security detail because of abuse she had received over her stance on climate change.
CBC said police were compiling daily reports on online threats against political leaders leading up to the 21 October federal election.