Longtime pot activist Jodie Emery said this is the first time in the 20-year history of Cannabis Day that the event has experienced any confrontation with police.
"The city has been so tolerant before," she said, speaking outside the Vancouver Art Gallery where the protest was being held. "I don't understand where this is coming from."
Bystanders said they witnessed officers descend on the gathering of hundreds of people around noon. A scuffle ensued before at least one man was led away in handcuffs.
Angry crowds chanted as they followed the officers around the street corner where they loaded a man into a police van.
Police initially said they had arrested two men but an email sent later in the day confirmed that four people had been arrested and that investigators expected to lay charges against each of them.
Spokesman Const. Brian Montague alleged in a release one of the men was "overtly" selling marijuana to minors and that he failed to stop after being warned.
"Police specifically informed (organizers) that the open selling or giving away of illegal items to young people could result in arrest," read the release. It added that police were especially concerned in the wake of April's 4/20 marijuana celebrations, which sent 64 people to hospital with symptoms including nausea and heart palpitations.
Officers were immediately confronted and swarmed while trying to carry out the arrest, said Montague.
Joshua Helsdon reported being pepper sprayed while recording the incident on his camera. He described police pulling and choking protesters who had encircled the marijuana vendor in order to prevent his arrest.
"I was 15 feet away when they decided to Mace me," said Helsdon, rubbing his red-rimmed eyes. "It's unbelievable, unbelievable."
Cannabis Day has taken place peacefully in downtown Vancouver over the past two decades.
In late June, the City of Vancouver sent Emery and her husband — pot activist Marc Emery — a cease-and-desist letter asking that the event be abandoned because it hadn't received have the necessary municipal permits. Organizers said they met with city officials and agreed to go ahead with the event on a smaller scale.
Cannabis Day event planners meet yearly with city officials, Vancouver police, Vancouver Fire and BC Ambulance Services to co-ordinate a safety plan, as well as raise money for toilets, security, first aid and fencing, said Emery.
"In recent years police have come to help us set up and then they stand back and they smile and wave at passersby," she said. "(But) for some reason the city has chosen to be confrontational and create an enormous problem where there never has been one before."
Emery speculated that the pressure behind this year's change could be coming from the federal government. She pointed to an "extraordinarily frosty reception" from Vancouver's deputy city manager Sadhu Johnston as out of the ordinary.
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