Parents are being warned not to allow children to play with BB pellet guns after armed police were called to a school in South Yorkshire.
Police say it is hard for officers to tell if a gun is a replica or real
Teachers at Edward Sheerien School in Barnsley called officers after a youth was spotted firing one of the guns.
Firearms officers confiscated the weapon and made it safe.
In a separate incident on Monday, Alex Cole, 12, died after being shot in the eye by an air rifle while playing with a friend in Conisbrough, Doncaster.
Of the incident on 26 April, Susan Hamby, head teacher at Edward Sheerien, said: "We contacted police to get them to explain to this lad the dangers of using this type of gun and guns in general."
Mrs Hamby added the school is working with police to stop youngsters playing with such weapons and said they were urging anyone with one to hand it in to police.
In February the force held a month-long weapons amnesty after a spate of shootings in the area.
In the first week alone more than 50 weapons including air rifles, shotguns, swords and knives were given to police.
Insp Andy Male said: "BB guns are seen as toys but it is illegal to take them out in a public place. They can be terrifying.
"They appear real, a trained firearms officer would not know the gun was a toy if it was pointed at them, nor would a member of the public."
Last week, police in North Yorkshire launched a campaign in the county after two fake guns were recovered from teenagers.
Assistant Chief Constable Peter Bagshaw said: "Every weapon being carried in these kind of incidents will be considered lethal until proven otherwise."