A school has banned parents from the grounds unless they have an appointment after some were violent and abusive towards staff.

The Ebbsfleet Academy in Southfleet Road, Swanscombe, has stopped pupils’ families from entering the site without prior arrangement after problems with a small minority of parents.

However the new rule, put in place this month, has been criticised by one parent who was unable to get into the grounds and take her own child to see a doctor.

Nicole Todd, 13, has health problems. She has been suffering crippling pains in her stomach for a few months.

Her step-father Terry Joseph said: “It’s hard for the doctors to know what’s wrong unless they see her when the pain sets in. When that happens, I try and get a last-minute emergency appointment at the doctors’.”

Mr Joseph, of Reed Court, Greenhithe, arranged an appointment at the Elmdene Surgery in Stone for 3.30pm after Nicole should have finished school. Her mum Clare Nottariami went to pick her up, but Nicole had been put in detention and the school refused to let her out.

Mr Joseph, 55, said: “Clare had to talk to them from an intercom because she wasn’t allowed on to the grounds, it was like Nicole was being imprisoned.

“They said they needed written proof of a doctor’s appointment. If you book a last minute appointment on the phone you don’t get that, but they didn’t care.

“Nicole can be a bit naughty but she’s not a troublemaker. She missed a previous detention so was made to stay after school. I support the school if they say she needs a detention but her health will always come first.”

Staff refused to budge and Nicole was kept back an hour, missing her appointment.

The statement on the door of Ebbsfleet Academy says: “Due to a small minority of parents who have displayed violent and abusive behaviour towards our staff, visitors will only be permitted into the academy by reception if they have a pre-booked appointment.”

A spokeswoman for the school said: “Following a recent incident, we have taken the decision to request that parents do not enter the premises during school hours unless they have prior agreement.”

The school has a messaging system to let parents know if their child is in detention, but Nicole’s parents were not informed that day.

HGV driver Mr Joseph said: “If Clare hadn’t been there for Nicole’s appointment, we wouldn’t have even known where she was. When you’re reading in the paper about a child being held at knifepoint outside a nearby grammar school, it’s a huge concern.

“Schools shouldn’t be able to over-ride the parent.”

In its statement, the school said: “Parents are still able to access the school reception to drop things off, collect something or if they have a pre-arranged appointment.

“We may request that proof of appointments is provided to take children out of school during detention.

“Any parent that would like to discuss the implications of the new system is welcome to contact principal Alison Colwell.”