We think he's on two.
4 seconds sound clip from the The Silence of the Lambs movie soundboard.
You can hear this line at 01:22:41 in the Blu-ray version of the movie.
Quote context
[...]
- Uh, roger, Lieutenant. Tate here.
- I'm on the elevator bringin' Pembry down.
- Uh, we're pretty sure he's somewhere on two, sir. That's all for now. Over.
- He's on the roof of the elevator.
- I see him. There's a gun by his hand. He's not moving.
[...]