Devon and Cornwall Police are to send two officers to Manchester to help provide cover during the funerals of PCs Fiona Bone and Nicola Hughes.
Chief Constable Shaun Sawyer said the officers would be sent to help police the city with the funerals due to take place at Manchester Cathedral tomorrow and Thursday.
Chairman of the authority Mike Bull, whose daughter is a serving officer with Greater Manchester Police (GMP), described it as "a very dark time" for the police service.
GMP's Deputy Chief Constable Ian Hopkins described the support offered to the force as "incredibly touching".
He added: "While we are not able to accept every kind offer of support, it would be a fitting tribute to our two colleagues if (the public) directed their support to their local officers, wherever they may be."
PC Bone, 32, and PC Hughes, 23, were killed in a gun and grenade attack in Greater Manchester as they went to answer a routine 999 call to a burglary. Dale Cregan has appeared in court accused of their murders.