Avon and Somerset Police are taking part in a minute’s silence to remember Pc Andrew Harper, who died while responding to a reported crime.
At 11:00am, Thames Valley Police and other across the country fell silent to honour the memory of the 28-year-old officer.
Pc Harper lost his life while investigating a reported burglary near Sulhamstead on the A4 in Berkshire on August 15.
Jed Foster, 20, has been charged with murder over the death.
Foster was one of 10 men and boys aged between 13 and 30 arrested following the incident.
The remaining nine have been bailed until 13 September.
A fundraising page set up by the Thames Valley Police Federation, which represents rank-and-file officers, had raised more than £260,000.
In a tribute, his widow Lissie Harper said her husband was “the kindest, loveliest, most selfless person you will ever meet.
“You were brave, funny, and always there for anyone who needed it.”
Ms Harper added that her husband loved being a police officer and “always wanted to keep everyone safe, especially me”.
She also thanked the public for the “overwhelming” support shown to her and Pc Harper’s family after his death.