Further details emerged about the murderous attack on the two officers, with one witness claiming PC Bone, 32, had her police issue taser gun in her hand when she was shot. Her fellow officer PC Hughes, 23, is believed to have attempted to run off to escape the gunman but had a grenade thrown at her before she was shot. She was seen lying in the road muttering for help, she died later in hospital, despite the efforts of paramedics and surgeons to save her. One eyewitness said: "I heard a bang that shook the house so I ran out and saw a woman on the floor who I could tell was already dead - there was blood all over her. It looked like she had been in a boxing ring. She had a taser in her hand and she was lay by the window of the house. I think that the younger officer tried to run away because she was further away from the house. She was lying there muttering for help. As colleagues of the two murdered officers mourned their loss yesterday with a minute's silence, police continued to question 29-year-old Dale Cregan on suspicion of their murder. Police revealed they had also arrested a 28-year-old man on suspicion of conspiracy to commit murder. Cregan is also being questioned on suspicion of the separate murders of father and son Mark and David Short earlier this year. Mark, 23, was shot in the neck while drinking in the Cotton Tree pub in Droylesden, Greater Manchester on May 25. Police yesterday confirmed that Cregan had been arrested on suspicion of the murder, but had been bailed pending further inquiries, because there was not enough evidence to charge him. However on August 10, Cregan was suspected of being involved in a gun and grenade attack in which Short's 46-year-old father David was killed. The victim was shot on the driveway of his home in Clayton, Greater Manchester, before his assailant threw a grenade under his body as he lay dying. Nine minutes later two men were caught on CCTV carrying out another grenade attack on a house three miles away. No one was injured. On the same day officers found a white Vauxhall van close to the scene of the second attack which bore the hallmarks of a grenade explosion inside. It is not clear whether the vehicle had been booby trapped or if a grenade had gone off accidentally. Police believe the grenades are former military weapons that arrived in Britain as part of a shipment from the former Yugoslavia and sources have said at least eight grenades were still on the streets of the city. It is thought yesterday's murderous attacks on the two police officers and the previous detonations mark the first time such weapons have been used by criminal gangs on mainland Britain. Conservative MP Patrick Mercer, a former army officer who served in Northern Ireland and Bosnia, said: "These grenades are readily available on the black market and easy to conceal on your person and use. We are seeing a move from explosives being used terrorist to being used by criminal gangs, which is extremely alarming. It introduces a completely different dimension into protection for police officers. What would concern me is if this starts to be copied by other gangs and individuals. Sir Peter said the police community across Britain was still struggling to come to terms with the loss of PCs Bone and Hughes. He said the force's main priority was to offer support to the devastated families of the two young officers. He said: "I would like to say how impressed we've been by the dignity of these families. Both have said how proud they were of Nicola and Fiona, and how proud those two officers were to serve the public. Both families have separately said that their loved ones died doing the jobs they loved. Tributes to the two officers continued to pour in last night with the Queen writing to Sir Peter asking him to pass on her sincere condolences to the families of both women. More than 25,000 messages of support had also been left on the force's website last night, something Sir Peter said meant a huge amount to all those who served in the police. Rank and file officers across Britain also showed their solidarity with many offering to provide cover for their colleagues in Manchester so that as many as possible can attend the women's funerals when they take place. Meanwhile at the scene of the attack in Mottram, forensic officers and teams of police continued to painstakingly examine the area as the investigation continued. Reports from locals suggested that despite being the subject of the biggest manhunt in Greater Manchester Police's history, Cregan had been on the Hattersley estate for some weeks and had even been seen drinking in local pubs. The force confirmed that they had carried out a number of armed raids in the area in local weeks following suggestions that Cregan was hiding out there. But Sir Peter told reporters that there was no specific intelligence to suggest that he was connected to the address in Abbey Gardens where PCs Bone and Hughes were murdered. Asked whether two unarmed female officers should have been answering emergency calls in the area when Cregan was at large, Sir Peter said: "We make no distinction between male officers and female officers, they do the same job." He added: "The nature of this inquiry means we have been making a huge number of inquiries across North Manchester and Tameside and there was clearly suspicion that Cregan was in that area. But we get hundreds of incidents every day in that area and it would be impractical to send armed officers to all of those incidents.