An eight-year-old boy was taken to hospital after falling victim to a prank when he was suffocated until he passed out . Police in Manchester have now issued a warning to parents over the game , known as 'sleeper ' , which officers say is potentially fatal . The child 's details have not been release but a Greater Manchester Police spokesman said the child is believed to have had underlying health problems and is expected to make a full recovery . Officers from Greater Manchester Police have been forced to issue a warning on Facebook ( pictured ) after an eight-year-old boy was hospitalised after a playground suffocation prank called 'sleeper ' went wrong . The 'sleeper ' prank involves a child having their nose and mouth held shut by another child until they black out from lack of oxygen . The youngster was treated in hospital on Wednesday after they were a 'sleeper ' victim , police said . Officers in North Manchester believe it is a new craze and have alerted parents . GMP 's North Manchester division posted on their Facebook site after the incident : 'Dangerous New Craze Warning - Attention all parents/guardians ... We have received reports of a new craze called 'Sleeper ' This involves children completely covering the mouth and noses of younger children until they completely pass out . Manchester 's city centre chief councillor Pat Karney ( pictured ) has said the craze must be stopped 'before we have a tragedy on our hands ' 'This is extremely dangerous , a child is currently in hospital being treated after falling victim to this game . Please advise every child you know and warn them of the dangers , this could easily lead to concussion or even death . The post has now been shared more than 11,200 times on the social network . GMP 's Facebook post received a flurry of responses from followers , some claiming the game dates back several years . Tasha Williams replied : 'This was happening when I was at school although it was someone pushing on your chest really hard or on your throat , it is a stupid game . ' Linzi Walker added : 'It 's not new it 's been going for years and years . ' But Pete James said : 'Only buzz I used to get as a kid was putting a crushed carton in the back wheel of my bike and making it sound like a motorbike ! What 's wrong with kids ? ? ' Stuart Roberts worte : 'Are the children of today total numbnuts ? ? ' Sebastian Ziola added : 'Back in my day , we played Pogs . Oh how times change . ' A senior council boss in Manchester has issued a stark warning about the craze . Pat Karney , councillor for neighbouring Harpurhey ward , told the Manchester Evening News : 'This news will put the fear of God in any parent or guardian . ' I will be talking to the council officers in the area to see how we can provide more information and warnings to local schools and parents . 'It has to stop before we have a terrible tragedy on our hands . The problem is that when kids hear about an incident like this , it goes viral in an instant in today 's world . Officers in Manchester ( GMP headquarters pictured ) believe 'sleeper ' is a new craze and have alerted parents .
Eight-year-old boy was hospitalised after being suffocated during 'game ' In it child 's nose and mouth are held shut by another until they pass out . Police in Manchester are warning that 'sleeper ' prank is potentially fatal . Councillor says craze must be stopped before 'we have a terrible tragedy '