Police were called to reports of someone making threats at a property in Sherwood Road in Keynsham at about 8.30am today.
The area was cordoned off and officers attended – including armed officers as a precaution.
A property was searched and the road closure lifted at 11am.
Officers also attended a property in Court Road in Kingswood as part of the on-going inquiries.
And following their attendance at a third property – in Blagrove Crescent in Hartcliffe – a man has been arrested on suspicion of threats to kill. He remains in police custody.