The Prime Minister has paid tribute to PCs Fiona Bone and Nicola Hughes and pledged to help police tackle organised crime.
Speaking on a visit to Greater Manchester Police's headquarters David Cameron said: "I wanted to come here to Manchester myself to pay my own personal respects to the two officers, the women police officers, who fell in the line of duty.
"I think the whole country is profoundly shocked by what has happened and it is right we praise the work that they did and remember all they have done.
"I think it's also important that the Government makes sure that it is doing everything it can to help the Greater Manchester Police force tackle organised crime and gang-related violence."
Mr Cameron also met relatives of both PC Bone and PC Hughes at the headquarters.
It was not disclosed exactly whom he met but he spoke to them in one room at the same time. It is understood the Prime Minister expressed a wish to meet the two families.
Greater Manchester Police Chief Constable Sir Peter Fahy also updated him on the investigation before he departed.