Northumbrian Water said the underwear was flushed down a toilet and caused a blockage in a sewage pipe in Middleton-St-George, near Darlington.

Heavy rain, together with a build up of grease and fat, caused the pipe to burst and the road above to collapse.

The road will remain closed for days and Northumbrian Water estimates repairs will cost more than £15,000.

The company has now urged residents to think carefully about what they flush away.

'Offending items'

A spokeswoman said: "If the underwear had not been flushed down the toilet, this would not have happened. It was very irresponsible behaviour.

These pipes are not designed to carry bras and knickers Northumbrian Water spokeswoman

"When we dug down to inspect the damage, we found a bra and knickers had snagged itself across the nine-inch diameter of the pipe.

"There was also a heavy build-up of grease and fat, which contributed to the situation. We were forced to repair a 2m section of sewer and a 10m section of road was affected.

"These pipes are not designed to carry bras and knickers."

The spokeswoman said it was impossible to trace the owners of the underwear.