HALIFAX -- More than a dozen people were arrested and released following a planned protest that prompted the closure of the Macdonald Bridge, which links Halifax and Dartmouth, Monday morning.

There was a heavy police presence on the Dartmouth side of the bridge for the protest, which forced many commuters to take alternate routes during the morning rush hour.

Members of the Extinction Rebellion previously announced their plans to block access to the bridge during the morning commute in an effort to raise awareness about what they say is a climate crisis.

“A lot of children and a lot of people from the younger generation, 20s, are not thinking they can have children because of the trauma of watching your children die from lack of water, lack of food or lack of air,” said Extinction Rebellion protester Tayla Paul.

Dozens of protesters like Paul waved flags and signs as they marched from a nearby transit terminal to the Macdonald Bridge toll plaza in Dartmouth, arriving around 7:35 a.m. Monday.

However, police closed the bridge to all traffic, including vehicles, bicycles and pedestrians, just before the protesters arrived, with officers blocking their access to the span.

“In consultation with our partners here at the Bridge Commission, a decision was made that, in the interest of public safety, it would be best that we close down the bridge,” said Const. John MacLeod, a spokesperson for Halifax Regional Police.

Several Halifax Transit buses were operating on detours Monday morning due to the bridge closure, with buses that usually travel on the Macdonald Bridge being rerouted to the MacKay Bridge.

The protest and subsequent bridge closure caused congestion on some main arteries throughout the Halifax and Dartmouth areas as motorists were forced to take alternate routes.

With the bike lanes on the Macdonald Bridge closed, many cyclists were forced to use the ferry, which only allows 12 cyclists on at a time. Some people waited in line for more than half an hour before snagging a spot on the boat.

“The cyclists are being disproportionately affected by, not the actions of the protesters, but by the police and other systems that are basically making it impossible for us to get back and forth,” said cyclist Brian Foster.

The incident also drew mixed reactions online and on the streets of Dartmouth, where one councillor expressed his anger over how the situation was handled.

“I think that they should move these folks – there’s a wide-open bridge here – and let people cross,” said Steve Streatch, the councillor for Waverley, Fall River, and Musquodoboit Valley.

“There’s 40 or 50 people here that have taken control and their agenda is leading there with the public who pay the bills to build this infrastructure to travel. It just doesn’t make sense to me at all and I completely disagree.”

The demonstration continued near the toll plaza for about three hours before the Bridge Commission asked police to clear the area so the bridge could reopen.

Just before 11 a.m., Halifax Regional Police gave the protesters 10 minutes to gather their things and leave the premises. Some protesters moved to the sidewalk, but some remained in the bridge lanes, prompting police to take action and make arrests.

“I think it’s really just an indication of the severity of the situation,” said protester Adam Baden-Clay. “We have decent, law-abiding people who are prepared to put their liberty on the line to really highlight and underscore how important this is.”

Police initially said they arrested 14 people under the Protection of Property Act for failing to leave the premises after being ordered to do so. However, they later corrected that number to 18.

Police say all 18 people were later released without charges.

The Macdonald Bridge reopened to all traffic shortly after noon Monday.

Roughly 40,000 vehicles use the bridge daily, along with about 1,200 people who bike or walk across the span.

The protest was just one of a number of actions happening across the country and around the world Monday.

Founded in Britain last year, Extinction Rebellion, also known as XR, now has chapters in some 50 countries. The group said Monday’s protests were taking place in 60 cities worldwide, including Toronto, Vancouver, Montreal, Berlin, London, and Madrid.

Members of the group usually sit or lie down in front of traffic until they are arrested and taken away by police officers.

With files from CTV Atlantic's Amy Stoodley and The Canadian Press