Engineers have been forced to use pickaxes to shift a “monster” 64m fatberg from sewers in Devon in an undertaking that is expected to last eight weeks.

Work has now begun on removal of the putrid blockage in Sidmouth created by oil, fat, and grease from wet wipes and other items that should not be flushed down toilets.

But heavy rain forced workers to suspend their efforts on Wednesday until water levels in the sewer became safe. They must use pickaxes and shovels to dislodge the hardened mass of waste, according to South West Water.

The company’s director of waste water, Andrew Roantree, said: ”The Sidmouth fatberg is the largest discovered in our service history, and [it] will take our sewer team around eight weeks to dissect this monster in exceptionally challenging work conditions.”

Following the discovery of the fatberg in January – the largest seen by the company – bosses urged residents only to flush toilet paper and their own waste, and not wet wipes or other items.

UK fatbergs in pictures Show all 7 1 /7 UK fatbergs in pictures UK fatbergs in pictures Sidmouth's 'monster' fatberg The blockage is 64m long AP UK fatbergs in pictures 64m fatberg in Devon This photo was released by South West Water AP UK fatbergs in pictures Workers tackle fatberg A fatberg is a mass of hardened fat, oil and baby wipes AP UK fatbergs in pictures On display A part of the Whitechapel fatberg on display in the Museum of London Museum of London UK fatbergs in pictures 130-tonne Whitechapel fatberg Authorities are tackling a huge fat blockage in the capital’s sewage system PA UK fatbergs in pictures Fatbergs by the numbers Data compiled by statistics agency Statista UK fatbergs in pictures Clogged mass A fatberg beneath Whitehall Thames Water

Cooking waste should go in the bin and not the sink, they added.

In 2017, a 250m fatberg was found in sewers beneath Whitechapel in east London.

A chunk of that blockage later went on display at the Museum of London.