POLICE have issued the "all-clear" following a mass evacuation of Gateway Academy this morning due to a bomb scare.

Hundreds of children were evacuated and a 14-year old boy arrested after an "explosive device" was reported to have been brought into the school.

The MOD and police were called to the school, in Marshfoot Road, Tilbury, at 11am this morning to deal with the device.  The explosive device brought into the school was described by one source, who did not wish to be named, as a "smoke bomb filled with nails."

A statement on the school website described the device as a "homemade smoke bomb" and said it was discovered by a teacher before being released.

Giving the all-clear, a spokesman for Essex Police said: "Experts attended the school and assessed the device as being safe and the incident was stood down at 3.20pm.

"A suspect currently remains in custody."

The spokesman added that experts had said "nothing harmful was coming from the device and that it was not going to do anyone any harm."

It has not yet been clarified by the police or the school whether or not the homemade device contained nails.

School head Grainne McLoughlin confirmed the boy had been suspended from school following the arrest.

No-one was reported to be hurt in the incident.

One onlooker at the scene this morning said: "It's chaos here, nobody knows what is going on.

"One minute we were told there was a fire drill the next thing we knew the police were here. All the children are out though."

A spokesman for Essex Police earlier this afternoon said: "Police have gone into the Gateway Academy in Marshfoot Road following reports that a pupil brought into school a suspicious device.

"The MOD have been contacted and an explosive ordinance disposal team called in to assess the device."

"The school has been evacuated as a precaution."

"A 14-year old boy has been arrested in connection with this incident and has been taken to Grays police station for questionning."

A statement from head of school Grainne McLaughlin on the school website said: "Today the Gateway Academy and free school were evacuated temporarily as a result of a student bringing a homemade smoke bomb on to the school site.

"The device was not released and discovered by a member of staff. The police advised that it should be taken as a serious matter. As a result the academy's evacuation procedures were enacted. The device was removed by the police and destroyed."

"We take the safety of staff and students as our highest priority and will never take risks in this regard. As for the young person in question, he will be subject to the disciplinary procedures of the GLC. It will be up to a panel of governors to decide his future at the academy. In the meantime, he will be suspended from the academy."