Maria Fernanda was on midnight guard duty when she claims to have heard a scratching sound coming from one of the lecture rooms.When she called her boss he told her to wait outside while he checked.
But seeing nothing unusual inside he told the 25-year-old not to worry and went back to his office.
Maria said: "No sooner had my boss gone than I heard the noise again.
"I pulled my service revolver out and went in and then I saw this black shadow flying across the room towards me.
"Before I could react it grabbed me and I screamed and ran full pelt to the bathroom where I locked myself in.
"I then noticed there was blood on my face, arms and chest and realised it had scratched me."
Other police officers have reported seeing a woman and girl covered in blood at the academy.
Read Full Story: Daily Star UK