The Temporary Chief Constable of Cumbria Police, Stuart Hyde, has been suspended from duty after a number of allegations of serious misconduct.
Cumbria Police Authority, which oversees the force, says the claims indicate there may have been "a breach in the standards of professional behaviour" in Mr Hyde's role as the force's chief.
The matter has been referred to the Independent Police Complaints Commission. The Authority would not comment further on the details of the allegations made against Mr Hyde.
He has been replaced with immediate effect by Bernard Lawson, which is a deputy chief constable at Merseyside Police.
Stuart Hyde became Temporary Chief Constable in January 2012, after serving as deputy for three years. He began his police career in Bristol in 1983, and has also worked at the West Yorkshire and West Midlands forces, including as a detective.
He is also a board member of the University of Cumbria and was awarded the Queen's Police Medal earlier this year.