The second man arrested in connection with the killings of two police officers is 28-year-old Stephen Garvey.
Garvey was arrested on suspicion of conspiracy to commit murder.
Officers nationwide have offered cover to colleagues in Greater Manchester Police so they can attend the funerals of the two killed PCs.
Manchester's police chief said he expected "developments" in the next 24 hours over possible charges relating to the deaths of two officers.
Over 50,000 tributes have been posted to Greater Manchester Police's online book of condolence to the two killed officers and Facebook page.