Two children appear to have been found living in the sewers in Washington state.

After lifting up an 80-pound manhole cover, Lakehaven Utility District workers found clothes, toys and food 14-feet underground.

One of two boys aged around 13 were reportedly spotted indicated the pair were living in the sewer system.

The discovery was made after meter readers spotted the manhole cover slightly open. They closed it and came back later to find it had been opened again, Kiro 7 reported.

Ken Miller, an engineering manager, said he had never seen anything like it in his 30 years of work.

“This should not happen at all," Miller told Kiro 7. "This is where all our waste goes from our houses and our businesses.

"No one should be down there ... this could have been life and death."

He also warned there was likely to be vermin and very limited oxygen in the sewer.