A group of University of Montreal students has been quarantined in China since Saturday. (CBC)China lifted a swine flu quarantine on a group of Canadian students Wednesday, two days early, after the measure was questioned by the Canadian government and world health authorities.

The 25 students and a professor from the University of Montreal — who travelled to the densely populated country last week to learn Chinese — were placed in a lakeside hotel after being pulled aside by provincial officials in Changchun after their plane landed in the northeastern city on Saturday. They were told they would be quarantined for seven days.

A Chinese official said the country will continue its strident checks on travellers from regions affected by an outbreak of the new strain of H1N1 flu, which is believed to have originated in Mexico.

Despite the restrictive measures, none of the group showed any symptoms or complained of feeling ill.

Patrick Martin-Menard, one of the quarantined students, told CBC News the students first heard the restrictions were being lifted from the Canadian consul, who called their professor earlier Wednesday to inform them of media reports he was hearing.

"We did not get any word from Chinese officials directly," Martin-Menard said in a telephone interview.

The group is scheduled to leave the hotel on Thursday morning, but Martin-Menard said they were finally allowed to step outside the hotel for the first time since Saturday.

"We were able to go outside and take a walk," he said.

Cannon to press Chinese for explanation

The decision to lift the quarantine shows local officials were obviously pressured by Beijing, the CBC's China correspondent Michel Cormier reported from the Chinese capital.

"This was starting to be quite an embarrassment for the Beijing national government," Cormier said.

"This was a local decision because the students had been allowed into the Beijing International Airport without any problems."

Canada's Foreign Affairs Department sent a diplomatic note on Tuesday seeking an explanation from China for placing the students under medical surveillance, even though none exhibited symptoms of the virus.

Speaking to reporters in Ottawa on Wednesday morning, Foreign Affairs Minister Lawrence Cannon said he would personally raise the matter during his trip to China on the weekend.

"I've asked for an explanation," the minister said.

The quarantine itself appeared severely flawed, as several students told CBC News they were in regular contact with hotel staff.

When asked by reporters about the World Health Organization's position on China's quarantine measures, the WHO's flu chief said Tuesday the organization was asking some countries to justify their disease control measures. But Dr. Keiji Fukuda refused to criticize China directly.

The students are eventually heading to the Northeast China Normal University and will spend another nine weeks in the country. Martin-Menard said the experience wouldn't sway them from their purpose.

"We're all going to continue what we came here to do," he said. "We certainly don't want all that has happened in the past few days to ruin the rest of our travel."

With files from The Canadian Press