Two men jailed for life for the murder of Pc Sharon Beshenivsky could face further charges after allegedly stabbing another inmate in his cell.
Muzzaker Shah and Yusuf Jamma are both serving a minimum of 35 years for the murder of the 37-year-old mother, who was shot dead on November 18 2005 when she responded to an alarm call at a Bradford travel agent.
Her colleague, Pc Teresa Milburn, was also gunned down in the street and seriously wounded as the robbers escaped with little more than £5,000.
The two prisoners have been questioned over an attack on an inmate who is also serving life for murder at Frankland jail in County Durham. The 22-year-old suffered stab wounds to the stomach and cuts to the face, police said.
A spokesman for Durham Police said two other prisoners were implicated in the incident. He refused to reveal the names of the accused, but they are understood to be Shah and Jamma.
The spokesman said: "A prisoner, aged 22, was reported to have been stabbed in his cell in Durham's Frankland Jail on the evening of March 6 at about 7pm. Statements have already been taken from members of staff.
"A file will be prepared for submission to the Crown Prosecution Service and they will decide what action to take, if any."
The victim was taken under armed police escort to Durham's University Hospital and was returned to the jail after treatment for stab wounds to the stomach and cuts to the face."
Following a trial last year Shah, 26, was told he must serve a minimum of 35 years in prison before he is considered for release after he admitted murdering the Bradford officer.
The judge told Shah, who was cleared of the attempted murder of Pc Milburn, and Jamma, who was found guilty of murder of Pc Beshenivsky, they were a danger to the public and might never be released.
