This urban explorer ventured into an abandoned mortuary located in Frankfurt, Germany, that dated back to World War II.

Upon entering the building, the filmer soon realised it had a very dark past.

"This particular mortuary was used to study the remains of disabled children and injured soldiers that were unwillingly euthanised at the neighbouring hospital between 1939 and 1941 as part of the Aktion T4 extermination trials," they told Newsflare.

"Although reports are varied, it's believed over 5000 children and 3000 soldiers passed through this particular mortuary before it was permanently closed in 1945 at the end of the war.

"Now, this old building slowly decays and rots, its dark history slowly fleeting away."

An urban explorer has captured incredible footage of an absolutely untouched abandoned mortuary in Germany that dates back to the early 1900's and which was used during the second world war.

This particular mortuary was used to study the remains of disabled children and injured soldiers that were unwillingly euthanised at the neighbouring hospital between 1939 and 1941 as part of the Aktion T4 extermination trials.

Although reports are varied, it's believed over 5000 children and 3000 soldiers passed through this particular mortuary before it was permanently closed in 1945 at the end of the war.

Now, this old building slowly decays and rots, its dark history slowly fleeting away.