Police believe a man spoke to a distressed woman in Branch Road, Lower Darwen, at approximately 2.30am on Saturday, April 8.
Officers on Tuesday (May 30) released CCTV footage of the man as they believe he could be a key witness in a rape investigation.
A spokesman for Lancashire Police said: “We want to speak to you about the nature of the conversation to get a fuller picture of what was said.”
It is believed the man was walking from the direction of the A666 along Branch Road towards Duchess Street.
The appeal came after a 33-year-old man from Blackburn was arrested on suspicion of rape.
If you are the man in the CCTV footage or if you know who he is, contact police by calling 101 or 01254 353553, quoting 426 of April 8, 2023.
