VANCOUVER -- One of the most popular annual races in Canada – and one of the country's biggest 4/20 rallies – have been called off over concerns about the growing COVID-19 outbreak.

Organizers of the Vancouver Sun Run announced Thursday that they have cancelled this year's event, which was scheduled to take place on April 19.

"This decision was not an easy one," race director Tim Hopkins said in a statement. "We are grateful to all of our volunteers, sponsors, suppliers and of course athletes for their understanding and support around this decision."

Not long after, marijuana activist Dana Larsen announced the city's massive 4/20 rally, scheduled to take place the day after the Sun Run, was cancelled as well.

"Though 4/20 is a protest, it is not a protest against health officials, and it makes sense to help them protect the public from the outbreak of an infectious virus," organizers said in a statement.

Earlier in the day, B.C.'s provincial health officer Dr. Bonnie Henry announced the government was asking organizers to cancel all events with more than 250 attendees.

The Vancouver Sun Run is the third largest 10-kilometre race in North America, with upwards of 50,000 people taking part some years. Organizers of 4/20 say they draw even larger crowds for the massive smoke-in at Sunset Beach.

Several other major events across North America have been called off, and a number of sports leagues, including the NHL and MLS, have suspended their seasons because of the outbreak.

4/20 rally on Sunset Beach