News reports say Andrew Bridgen, a lawmaker who holds the North West Leicestershire seat, was taken into custody in relation to the alleged assault early Thursday.
Police did not confirm the identity of the man taken into custody, but said he was bailed out to return on a date in mid-July.
Bridgen, a former Royal Marine, was elected last year. He is described as “Eurosceptic” for his criticism of European Union regulations. He is married and a father of two.
The Conservative party refused to comment on the incident, saying it was “a matter for the police.”