OTTAWA -- The "Rolling Thunder" protest in the national capital over the weekend cost an estimated $2.5 to $3 million to police, says the chair of Ottawa's police services board.

Eli El-Chantiry said police are expecting more convoy protests in the future and a sustainable solution needs to be found.

Protesters arrived Friday afternoon as part of the "Rolling Thunder" rally, organized by Freedom Fighters Canada, a group dedicated to speaking out against COVID-19 mandates.

El-Chantiry said the police, including officers brought in from outside the capital, were prepared for every eventuality and had intelligence about the bikers and their plans.

But less was known about the intentions of other protesters not part of the core group who arrived in pickup trucks, big rigs, cars and camper vans.

"That group -- we don't know who's who," El-Chantiry said in an interview.

The relatively peaceful protest could have escalated if officers had not been so well-prepared, he said.

"It could have gone the other way easily," he said. "A lot of people were denied entry to the downtown with their vehicle."

Ottawa police called in more than 800 reinforcements from RCMP and other forces to help, including by blocking off highway exits and streets in the downtown core to prevent an encampment forming.

El-Chantiry said the police also had rapid response teams on hand. Police with riot shields were deployed on Friday evening in downtown Ottawa.

The chair of the police board, which oversees the police service, said he had been briefed by interim chief Steve Bell.

Bell was not available for an interview on Monday.

Over the weekend, 10 people were arrested, including seven who had taken part in the earlier "Freedom Convoy" protests and had breached court orders banning them from returning to Ottawa, El-Chantiry said.

The Ottawa police said in a statement the arrests pertained to different Criminal Code offences, including breach of conditions, assaulting police and causing a disturbance.

The statement added that all traffic restrictions had been lifted, including blocked-off roads in the city centre.

Ottawa police drew lessons from the protests in February when throngs of protesters opposed to COVID-19 public health measures and the federal government choked Ottawa's streets for weeks, the board chair said.

But the protests are evolving and different in nature and Ottawa police need to be ready, he said.

"One size does not fit all," El-Chantiry said. "This could happen any time, so we have to prepare and have the resources."

The federal government has agreed to foot the $35 million bill for policing of the three-week "Freedom Convoy" protest in February.

The occupation prompted the Trudeau government to invoke the Emergencies Act for the first time and ended after hundreds of police officers moved in to disperse the crowds, making dozens of arrests.

The board chief said a plan -- including a financial plan -- was needed to deal with future protests, which show no sign of stopping.

"We have to find a sustainable way to do this," he said. "I will be working with the federal and provincial government to find a sustainable way for the future."

It's important for the people of downtown Ottawa to be able to enjoy their city without constant disruption, El-Chantiry said.

"I am trying to find a way to sustain that cost and want the community who live there now to enjoy their summer and their home."

This report by The Canadian Press was first published May 2, 2022.