Here's what we know so far.
CrimeChesterfield counter terrorism operation - what we know so farFour men, including a 31-year-old from Chesterfield, have been arrested as part of a counter terrorism operation this morning.By The NewsroomPublished 19th Dec 2017, 14:03 BSTUpdated 19th Dec 2017, 14:10 BST The Army's Bomb Disposal Team has been at a property in Chesterfield.Here's what we know so far.