An estimated 250 million bees escaped from an overturned truck in the US state of Washington on Friday, sparking warnings from authorities for the public to avoid the swarm of stinging insects.

Emergency officials were helped by several master bee-keepers after the truck, which had been hauling roughly 70,000 lb (31,750 kg) of active honey bee hives, flipped over on a road near the Canadian border.

“The goal is to save as many bees as possible,” Whatcom County Sheriff’s Office (WCSO) said shortly after the incident.

The authorities said the site of the crash would remain closed “until the rescue is complete”.

“250 million bees are now loose,” wrote Whatcom County Sheriff. “AVOID THE AREA due to the potential of bee escaping and swarming”.

Bee-keepers worked with police “to assist in re-setting the box hives”, containers bee-keepers use to house honeybees.

“The plan is to allow the bees to re-hive and find their queen bee,” WCSO said, adding: “That should occur within the next 24-48 hours.”

In an update posted to social media later on Friday, police thanked “the wonderful community of bee-keepers”, saying “over two dozen” had turned up to help with the rescue efforts.

“By morning, most bees should have returned to their hives,” WCSO wrote on Facebook.

Footage shared by police showed huge numbers of bees swarming around the overturned lorry.

While some bee-keepers aim only to produce honey, many others rent out their hives to farmers who need the insects to pollinate their crops.