Peter Tobin, a Scottish serial killer serving life in prison, is understood to be recovering in hospital after being attacked.
Tobin, 68, who was convicted in 2006 of murdering three young women, was assaulted at HMP Edinburgh yesterday. The Scottish Prison Service confirmed an incident had been reported to police.
Tobin is serving a life sentence for raping and murdering Polish student Angelika Kluk, 23, and hiding her body under the floor of a Glasgow church.
He was also convicted of murdering 15-year-old schoolgirl Vicky Hamilton, of Redding, near Falkirk, in 1991, and 18-year-old Dinah McNicol in the same year.
Their bodies were found 17 years later, buried in the garden of his former home in Margate, Kent.
Scottish police set up an investigation to try and link Tobin to other unsolved murders, but the operation was wrapped up in 2011 without success.