Essex Police have advised people in Colchester not to visit isolated places alone, after two fatal knife attacks in the town in three months.
Nahid Almanea, 31, was found on Saturday near the University of Essex campus. She had been stabbed 16 times.
James Attfield, 33, was stabbed 100 times in Castle Park in March.
Police say a man in his fifties is helping them with their inquiries.
More top news
A list of commemorative events as the UK marks a decade to the day 52 were killed and hundreds injured in London terror attacks.
Larger stores could be allowed to open beyond the current six-hour limit on Sundays under a relaxation of rules in Wednesday's Budget.
IS is now attracting women and whole families as well as young men - but will any return to carry out another 7/7?