The officer and the other victims were taken to the hospital for treatment of multiple injuries, police in the western Canadian city said.
"Two victims have been stabbed to death", regional police chief Olivier de Mazieres said.
France has experienced dozens of Islamic extremist terror attacks over the last two years.
Meanwhile, France's counter-terrorism prosecutor has opened an investigation into the attack, but said no motive had been immediately given.
French football game is abandoned after safety barrier collapses
Television pictures showed dozens of fans falling onto the pitch, and the match was suspended following a security meeting. The incident occured in the 15th minute as the visiting fans celebrated Fode Ballo-Toure's scoring the opening goal.
The knife attack is being investigated by France's anti-terror prosecutor. But officials also took pains to emphasize the circumstances of the attack were far from clear.
The assailant was shot dead by a soldier from a military Sentinelle patrol, a force deployed across the country as part of a state of emergency declared after Islamist attacks that began nearly two years ago.
A soldier shot and killed the attacker after the stabbings.
In August, a driver deliberately rammed into two Marseille bus stops, killing a woman, but officials said it wasn't terror related.
"Operation of ongoing police avoid the sector", the tweet said in French.
Manchester City confirm Benjamin Mendy has ruptured ligaments
French defender Benjamin Mende was injured by a cruciate ligament in the right knee after the player underwent tests. Manchester City held off Shakhtar Donetsk 2-0 to win their second straight game to open Group F.
The main suspect in a Marseille attack in which two women were stabbed to death had been arrested and let go in Lyon two days before the assault at the train station, authorities said. "I heard someone shout "Allahu Akbar" and I saw a man who seemed to be dressed all in black".
France has been repeatedly targeted by ISIS and has been active in the anti-IS coalition since 2014. The train station partially reopened in the late afternoon.
One had her throat slit and the other was stabbed in the chest and stomach.
New President Emmanuel Macron has vowed to end the state of emergency with a new and controversial security law that will make numerous provisions of the emergency regime permanent.
Thousands of emergency supply containers are trapped at Puerto Rico's port
He said getting aid where it was needed has been a challenge because of the magnitude of the destruction on the island. Rather, the DHS is presently reviewing a waiver request submitted by eight members of Congress, led by Rep.
The Saint-Charles station is a similar one where four Americans contemplating overseas succumbed to corrosive assaults a month ago.