OTTAWA, Nov 12 (Reuters) - Canada"s spy service said on Friday it was increasingly concerned about the rise of violent ideologically motivated online rhetoric, which it blamed in part on tensions caused by the COVID-19 pandemic. The Canadian Security Intelligence Service (CSIS) said since the start of the pandemic, threats posed by extremists had "evolved with unprecedented multiplicity and fluidity". COVID-19, it said, had worsened existing strains of xenophobia and anti-authoritarianism. Violent extremists were exploiting the pandemic by amplifying false information about government measures and the virus, it said. Protesters opposed to mandatory vaccinations have blocked access to hospitals across Canada and abused medical staff, both in person and online.Online rhetoric that is increasingly violent and calls for the arrest and execution of specific individuals is of increasing concern," CSIS said in a statement. CSIS said that since 2014, people motivated in whole or in part by extremist ideological views had killed 25 people and wounded 41 in Canada. This was more than those motivated by religious or political extremism. In June, four members of a Canadian Muslim family were run over and killed by a man in a pick-up truck in an attack the police said was driven by hate. read more