Four workers who went up to an overhead reservoir of the public health engineering department in Jalpaiguri’s Nagrataka on Tuesday to clean it were attacked by bees from eight beehives on the tank’s outer surface.

The workers were forced to hide inside the tank. A fireman who went to their rescue met with the same fate.

All five crouched inside the tank for five hours and came out only after the beehives were torched.

Sources said that as Nagrakata residents who get water from the reservoir at Panitanki More in Sukhanibusty complained of poor supply, the PHE hired contractual workers to clean the reservoir.

When workers cleaned the tank on Tuesday morning, the bees did not disturb them. But around 1pm, when four workers went up to the tank again as the flow of water was poor, the bees apparently lost their cool.

Biswajit Das, Pabitra Das, Papai Bala and Biswajit Sarkar, who were attacked by hundreds of bees, scrambled inside the tank for safety.

“They were lucky the tank only had knee-deep water,” said Krishna Roy, a worker who had not climbed up the tank.

As news spread, a team from the fire services department arrived to rescue the quartet. When fireman Rintu Sarkar reached the tank, angry bees stung him too. He joined the four workers inside the tank.

Finally, BDO Bipul Kumar Mondal, Nagrakata police and Jalpaiguri Zilla Parishad mentor Amarnath Jha decided to hire experts who collect honey from beehives. Policemen made public announcements, asking onlookers to leave and nearby residents to keep doors and windows shut.

Around 5.30pm, experts Mirbahadur Chhetri and Radhe Chhetri used bleaching powder, garlic and fire to clear the beehives. Around 6pm, the five men came out of the tank, said the BDO.