- It's a warship.
- What? Here? Can you identify?
- It's a frigate, U.S., probably Perry class. He's signaling.

8 seconds sound clip from the The Hunt for Red October movie soundboard.

You can hear this line at 01:44:45.119 in the Blu-ray version of the movie.

Quote context

[...]

- Make sure the count is accurate, Doctor. We must get the entire crew out.

- Yes, sir.

- Master-At-Arms reports rafts secure and evacuation proceeding.

- Very good.

- We'll rotate through the conn. No officer will spend more than 20 minutes below deck.

- Will that be satisfactory, Doctor?

- Completely, Captain.

- Surface contact! 2-7-0. Six miles and closing fast.

- It's a warship.

- What? Here? Can you identify?

- It's a frigate, U.S., probably Perry class. He's signaling.

- Red October, Red October. Halt and stay where you are. Do not attempt to submerge, or you will be fired upon.

- Captain, I think he means to board us.

- You will go with the crew. The officers and I will submerge beneath you and scuttle the ship.

- You'll receive the order of Lenin for this, Captain.

[...]