Hundreds of pupils were evacuated and 23 people treated by medics following a chemical leak at a Kent school this morning.

Pupils were sent home from Ebbsfleet Academy in Swanscombe after the buildings were evacuated "for a considerable amount of time" at 10.30am.

Eight children and 15 adults were treated by medics after the "bleach-like" smell spread from a kitchen extraction system.

Those affected suffered from coughing, runny noses and itchy eyes, and two adults are likely to need further treatment in hospital.

A spokesman for South East Coast Ambulance Service added: "We are likely to be taking two adults to hospital, but they haven't left the scene yet and are not thought to be in a serious condition.

"We have treated 23 patients, including eight children, but are staying at the scene to monitor the situation.

"The symptoms include coughing, runny noses and itchy eyes."

In a statement, headteacher Alison Colwell confirmed that there had been a minor chemical incident and that pupils were evacuated for an hour.

She said: "As you are no doubt aware, we have had to close the school early today due to a minor chemical incident that meant we had to evacuate the building.

"Students and staff had to remain outside for an hour and a half whilst the fire brigade, police and specialist hazard officers investigated and monitored the situation.

"Despite the cold weather, the students were impeccable in their sensible behaviour. When we were finally given permission to enter the building, the situation was explained fully to pupils and staff.

"In the interests of the welfare and wellbeing of students and staff I made the decision to close the school for the remainder of the afternoon.

"All pupils were given lunch if they wanted it before they left, and any student who was not able to or did not wish to go was allowed to stay in school."

Parents were told their children were being sent home after emergency services rushed to the site.

It is now thought the source of the leak was a kitchen extractor.

An email sent to parents from the school said: "Due to a chemical incident, the school building evacuated today for a considerable amount of time and emergency services were called.

"We have taken the decision to send students home shortly as we feel it is in their best interests and have asked that they contact parents / carers to advise of their planned route home.

"Students will be given the option of remaining here until 3.30pm.

"The building will be fully open as usual tomorrow."

A South East Coast Ambulance Service spokesman said the majority of people checked over were not in a serious condition.

A Kent Police spokesman said: "Kent Police has assisted crews from Kent Fire and Rescue Service while they responded to a suspected chemical leak at a school in Southfleet Road, Swanscombe.

"The incident was reported at 10.30am on Wednesday January 10.

"The school was evacuated as precaution."

Firefighters said the odour is believed to have come from a kitchen extraction system in the plant room, and it is now being ventilated.

A Kent Fire and Rescue spokesperson said: "We were called to Ebbsfleet Academy in Southfleet Road, Swanscombe, just before 10.30am to reports of a bleach-like smell in a plant room.

"As a precaution, pupils and staff were evacuated from the building while KFRS' specialist detection and monitoring team investigated.

"South East Coast Ambulance Service also attended the scene and assessed a number of patients.

"The source of the smell is thought to have been a leak from kitchen extraction system in the plant room and the plant room is now being ventilated by fire crews."