Police are investigating reports of youths urinating into bowsers of drinking water in a flood-stricken town, as squabbling over the scarce water supplies intensified last night.

Gloucestershire police said that they had received a dozen complaints of contamination of drinking water bowsers in Cheltenham, several of which concerned teenagers urinating into the containers.

“The advice is that the water needs to be boiled anyway. We’re investigating every allegation,” a spokeswoman said. One resident, who asked not to be named, said it was “plain sick” for youngsters to think it was a joke.

In Gloucester, Tewkesbury and Cheltenham tempers frayed as hundreds of bowsers deployed across the towns ran out of water. It prompted complaints that they were not being refilled quickly enough and that some people were behaving antisocially by hoarding water.

One woman in Gloucester, who asked not to be identified, said: “I came down here five times yesterday and there was nothing. My neighbours said they saw a builder’s lorry come and take away ten gallons. We can’t put up with much more of this.”

Fraser Pithie, senior operations manager of Severn Trent, said: “The antisocial behaviour of some of these people is making a bad situation even worse. We have a national emergency on our hands. People are being too greedy.” Police said that one bowser out of the several thousand in the town had been stolen and returned empty.

Conmen claiming to work for the local council are also using the water crisis to prey on the vulnerable and elderly. One gang walked into a house, saying that they were checking the water supply, and stole £400 from an 87-year-old man.

Severn Trent gave warning that it could still take up to two weeks to secure the flooded Mythe treatment plant and restore the water supply.

Thousands of litres of water have been flown from Germany by a humanitarian group. Scottish Water promised last night to step up its effort to help flood victims.

The company has diverted five of its drinking water tankers south of the border. It hopes that the tankers, carrying 81,000 litres (17,800 gallons), will arrive this evening.

One of the five vehicles is a smaller tanker, which is more manoeuvrable and will supply communities with limited road access.

Mark Murphy, of Scottish Water, said: “When the disaster happened, we immediately offered our support. We are happy to respond to Water UK’s mutual aid scheme to help out in any way we can.”