First you're gonna need a fully loaded bazooka. Walk into the hospital with the weapon and start to shoot.

Shoot at the windows, doors, anything only with bazooka. Then go down to the hall and shoot the bazooka some more.

Make sure everyone in the hospital is dead. When everyone is dead throw a bomb down the hall.

Then just walk around the hallway. Then if you keep doing it you'll see a dark figure of a man.

He will look all ghost like you can put your hand right through him.

This should work. It has worked for me.

[unconfirmed]