Under the league's Phase 2 plan, clubs that met safety criteria were allowed to reopen training facilities for voluntary workouts with groups of no more than six players at a time, as of June 8.
The NHL has been working toward resuming its season after it was halted in mid-March due to the coronavirus outbreak, with an expanded 24-team playoff format in two hub cities that have yet to be determined.
The NHL said that more than 250 players reported to club facilities as of Monday and had been tested more than 1,450 times for COVID-19. The league said 11 other players "outside of the Phase 2 protocol" also tested positive.
"All Players who have tested positive have been self-isolated and are following CDC and Health Canada protocols," the NHL said.
A flurry of positive tests among athletes have dented hopes for the return of professional sport in North America. The Tampa Bay Lightning reportedly reopened its facilities last week after briefly shutting down due to positive tests among players and some staff members. (Reporting By Amy Tennery Editing by Christian Radnedge)