A Merseyside prison run by private-firm G4S has been "slow to react" to increasing levels of violence and has failed to address links to the availability of drugs - including so-called legal highs, inspectors have found.
HMP Altcourse, in Liverpool, has been criticised by Her Majesty's Inspectorate of Prisons for its "inadequate" response to the violence - which included 210 assaults, including 53 against staff - in the previous six months.
Between January and April alone, 38 serious assaults were recorded. Gang issues and the availability of drugs, particularly so-called legal highs such as Spice and Black Mamba, were a significant factor in much of the violence, inspectors added.
The prison's response to this was inadequate at both strategic and operational levels.
"The prison had been slow to react to the increasing levels of violence which, to some extent, had become normalised.
"The security strategy did not make the necessary links between drugs, gangs and violence and little had been done to address the disproportionate number of young adults involved in violent incidents."
Elsewhere, inspectors found the use of force was not always "proportionate and necessary", while the jail was overcrowded with "many squalid cells" designed for one or two holding an additional prisoner.
Chief inspectors of Prisons Nick Hardwick said tackling violence at the Category B prison, which holds up to 1,133 inmates was "the urgent priority" for Altcourse.
The urgent priority for Altcourse is to reduce the high levels of violence.
"The prison needs to ensure it does this without damaging its longstanding strengths of positive relationships between staff and prisoners and good purposeful activity, which are critical if prisoners are to leave Altcourse with decent opportunities in order to lead law-abiding lives in the community."
G4S runs four other prisons in the UK - Birmingham, Oakwood, in Wolverhampton, Parc in Bridgend and Rye Hill in Rugby.
More top news
Susan Pain, an insurance broker, used her inside knowledge of the industry to submit 31 false claims that led to pay outs worth £142,334.
A machete wielding duo left a postmaster in hospital after an armed robbery at a post office in Bolton.
At around 9.30pm police were called to reports that a 14-year-old boy had been assaulted at a take-away on Ashton Road in Denton.