People throwing snowballs could be prosecuted for assault in cases where they are used to attack people causing injury, police have said.
People are told enjoy the snow but be sensible about the dangers
More than 100 calls about snowball incidents were reported to south east Kent police in 24 hours.
Ch Insp Paul Wilczek said he had not checked if the snowballs had contained stones, but experiences of past years had led him to warn of the dangers.
He said snow had begun to harden into ice, and warned people to be sensible.
Civil rights group Liberty said if snowballs contained stones or rocks, then police were not being unreasonable.
"If it is a case of Kent Police going over the top and saying people can't snowball, that would be silly and a waste of time," a spokesman said.
"But we don't have a problem with police warning people about putting stones in snowballs and using them to attack people. It is common sense."
Ch Insp Wilczek said there were concerns that snowball-throwing could cause injury or damage.
"We are advising people to be aware of potential dangers especially when there is a lot of ice about, and bear in mind that other people might not think it's funny."
He added: "Some people think it's funny to insert a stone inside a snowball and hurl it at cars - we don't.
"If it is reported to us and offences are made out, we will look to pursue the offenders."