Amateur video filmed by a guest at a Las Vegas hotel is attracting hundreds of thousands of hits on the internet.

Filmed from behind a protective window, the guests watched as two trainers entered a lion's cage.

What starts out as a normal holiday video quickly turns into a shocking scene as the lion lunges at one of the men.

The trainer escapes to safety, seemingly unscathed.

The video has been watched almost half-a-million times since it was uploaded to the popular video sharing site Youtube earlier his week.