WESTPORT — An afternoon rooftop fire at the historic National Hall building was quickly quelled by firefighters Tuesday afternoon. (Photos by Jarret Liotta)

Water that had put out the fire on the National Hall roof, at left, ultimately flowed onto the Post Road, where cold temperatures made it freeze. Firefighters waited for the state Department of Transportation truck to come and salt the roadway.

Police cars close the eastern side of the Ruth Steinkraus Cohen Bridge on Route 1 to traffic.

After putting out the fire, firefighters roll up one of the hoses used onto the truck parked on a closed off Wilton Road.

The state DOT truck salts the Post Road, where the runoff of the water used to douse the fire reached the road and froze.

The nearby Wilton Fire Department sent help over to Westport as part of a reciprocal arrangement between departments.

Despite the intersection being blocked by emergency vehicles, this EMT had to jump in front of an SUV coming east down the Post Road that crossed onto the other side and tried to turn left into a closed-off Wilton Road …

and then did a departing U-turn …