Demolition experts in Denmark were left red-faced when a massive silo tower fell the wrong way, crushing a library and and a music school.

Large crowds had gathered to witness the destruction of the imposing 174ft (53m) structure in Vordingborg, southern Denmark, that had been a major landmark for 36 years..

But when the carefully laid 10kg of explosives were triggered - and the gathered spectators began to cheer - the experts hired to complete the demolition could only look on in in horror as the concrete structure crashed the wrong way to the ground, hurling rubble and dust onto a neighbouring waterfront library and music school.

Fortunately, no one was injured in the accident.

"I simply do not know how it may have gone so bad," blasting manager Kenneth Wegge told Danish news network TV East. "I will put my head on the block."

An investigation is under way into what caused the operation to go wrong.

In the explosives industry, a building that does not go down in the way it was supposed to is known as a "standup".