HALIFAX - Fire officials say a natural gas leak in a Halifax neighbourhood has prompted the evacuation of about 550 homes and businesses.

Deputy fire Chief Roy Hollett says a construction crew working on Portland Street in Dartmouth punctured a 15-centimetre natural gas main at around 8:30 a.m. today.

Hollett says the evacuation zone is large because of the size of the gas main that was punctured.

The city says students at Prince Arthur Junior High and Southdale-North Woodside School have been told to remain inside until the leak is contained.

Halifax Transit buses are providing shelter for people who have been evacuated from their homes or businesses.

No injuries have been reported.

Hollett says Heritage Gas is working to pinch off the line and contain the leak, but the evacuation won't be lifted until natural gas levels in the air return to normal.