HALIFAX -- Police in Halifax have arrested six people outside a Canada Post sorting facility in the city's north end.

In a statement Sunday night, police say protesters at the facility were posing a "serious public safety threat" and not complying with officers' attempts to disperse them.

They say they responded to reports that several vehicles were clogging up traffic on a street near the facility, "impacting two-way traffic."

The force says it "respects and upholds the right of citizens for peaceful and safe protest," but officers acted in the interest of public safety.

Protesters have been rallying outside Canada Post facilities throughout the weekend, after the federal government legislated postal workers back on the job.

In a statement Saturday afternoon, Canada Post said it had contacted police about a similar rally in Mississauga, Ont., and was considering its options to deal with the demonstrations.