Coronation Street actor Bill Roache who plays Ken Barlow has been arrested on suspicion of raping a 15-year-old girl in 1967.
The star, 81, was held at his home in Wilmslow, Cheshire, this morning.
Roache faces an allegation of raping an under-age girl in Lancashire between April and July 1967.
A spokesman for Lancashire Police said: "An 81-year-old man from Wilmslow in Cheshire has this morning, Wednesday May 1 2013, been arrested by Lancashire Constabulary on suspicion of rape.
"The man will be interviewed at a police station in Lancashire during the course of the day.
"We take all allegations of sexual abuse extremely seriously and would encourage people with any information about sexual abuse, or anyone who has been a victim of sexual abuse, to come forward and report their concerns confident in the knowledge they will be investigated appropriately and with sensitivity."
An ITV spokeswoman said the broadcaster was not in a position to comment, but it is understood Roache will not appear in the soap while investigations continue.
Sky News Crime Correspondent Martin Brunt said: "According to neighbours, plain clothes police arrived at his home in Wilmslow at around 8am. His home is being searched and police are questioning him about historical allegations."
Roache has appeared in Coronation Street for more than 50 years. According to his website, he is the world's longest-running television actor.