Conservative leadership hopeful Peter MacKay is facing blowback after posting — then deleting — a tweet that expressed support for counter-protesters who dismantled a barricade erected by supporters of the Wet'suwet'en hereditary chiefs near Edmonton on Wednesday.

"Glad to see a couple Albertans with a pickup truck can do more for our economy in an afternoon than Justin Trudeau could do in four years," the tweet read.

The tweet was a reference to Wednesday's confrontation between a group of counter-protesters and some anti-pipeline demonstrators who had set up a blockade on CN's main rail line in the western part of the provincial capital.

After a provincial court granted an injunction against the protesters, the counter-protesters removed material that was blocking the railway and dismantled a wooden makeshift barrier the anti-pipeline activists had built.

In this tweet sent from Peter MacKay's account, the Conservative leadership candidate appears to applaud the efforts of counter-demonstrators to dismantle a blockade of train tracks in Edmonton. (Peter MacKay/Twitter)

Critics denounce vigilantism

Critics quickly denounced the tweet as inappropriate because they said it appeared the former justice minister was promoting vigilantism.

Sean Carleton, a historian at the Mount Royal University in Calgary, said it's dangerous for politicians in positions of influence to support people taking the law into their own hands.

"I think it kind of legitimizes this more vigilante approach," said Carleton. "I would hate for those kind of comments to embolden the wrong kind of people trying to take this into their own hands and risk making things worse ..."

MacKay's tweet on the rail blockade was eventually deleted and replaced with a new, three-part message.

"I see this as an act of good citizenship. The peaceful removal of debris deliberately placed on a railway that posed a threat to public safety," reads one of the new tweets.

"I stand with the workers, producers and suppliers who work hard, obey the law, care for their neighbors and keep Canada the best place in the world to live."

Hours after that thread hit MacKay's Twitter feed, he tweeted out a statement denouncing both the protests and those engaged in the "peaceful removal of debris" from railways.

"Illegal blockades and vigilante reactions by those frustrated by the Prime Minister's inaction are dangerous," MacKay wrote. "We need leadership, not platitudes, to resolve this crisis."

MacKay went on to say that when he is prime minister, "progress will not be accomplished with professional protesters shutting down the Canadian economy and harming innocent people who are trying to make ends meet."

Please see my statement today on the illegal blockades: <a href="https://t.co/eMaAvYpdSo">pic.twitter.com/eMaAvYpdSo</a> —@PeterMacKay

Second social media controversy

The social media dustup isn't the first time MacKay's leadership campaign team has run into trouble on social media.

On Feb. 3, MacKay backtracked on a tweet attacking Prime Minister Justin Trudeau for expensing $876.95 in yoga sessions and spa bills while running for the leadership of the Liberal Party.

MacKay, who has said he wants his campaign to maintain a civilized tone, said he was unhappy with the personal nature of the tweet and made that known to his team, although he refused to take it down.

The MacKay campaign addressed the rail blockade tweets in a fundraising email sent out on Thursday that repeated the message from the now-deleted tweet.

In a statement released on Thursday, MacKay called for a swift end to the rail blockades.

"The prime minister has left Canadians feeling like the government has lost control and is paralyzed in its inability to act," said MacKay. "Nobody is above the law. The prime minister and the police need to do their job, and that is restoring peace and order. Leadership is, after all, about making hard decisions and taking decisive action."

Tough words from the candidates

Other Conservative leadership candidates have taken a hard line on the blockades.

Erin O'Toole, MP for Durham, told the National Post that he would criminalize the act of blocking critical infrastructure, including railways, and give police the power to clear protesters without an injunction.

Marilyn Gladu, MP for Sarnia—Lambton, told a local newspaper that the federal government should call in the military to enforce court injunctions if "the RCMP can't handle it." Those comments provoked a similar backlash.

Carleton warned against resorting to force to end the blockades.

"These macho calls for aggression and kind of a might-is-right approach ... we've seen that, even just in the last 30 years in Indigenous-settler relations, [they can] go very sideways," he said.

When asked about the Edmonton incident during a press conference on Parliament Hill today, Public Safety Minister Bill Blair said the situation should be resolved by peaceful means.

"I always advocate for adherence to the rule of law and peaceful resolution of these disputes and we'll continue to support that," Blair said.