An investigation has been launched to track down the "mole" who spilled the beans over secret plans to close a city school.

Chiefs at Brighton and Hove City Council were furious last month when we revealed the plans to shut East Brighton College of Media Arts before pupils and teachers had been told.

Now an inquiry is under way to trace the source of the leak.

But all lines of investigation have so far drawn a blank and, since we have a duty to protect all of its sources, it is likely the identity of the source will remain unknown.

Tony Miller, spokesman for the council, said: "We weren't very happy that at that stage confidential information had been given out.

"We have not been able to find out who leaked it and I don't think we ever will."

A tip-off to The Argus exposed the plan but council bosses claim reporters from the BBC knew about the shock closure several days earlier and neglected to report it.

Our inquiries forced the council to go public.

The announcement prompted a backlash from teaching staff, parents and unions who were concerned they were being told through the Press.

Mr Miller said there had never been any intention to keep the news a secret but they had wanted to speak to parents, staff and governors first.

He said: "This is not us trying to keep it out of the public domain but we recognise there were people who have a right to know before it's published.

"At that stage very few people knew and it's difficult for us because certain people read it first in the Press and we got it in the neck.

"They wanted to know why we hadn't told them first.

"We were planning to tell all the key people in a sequence from the governors meeting on Thursday night, an early morning meeting for the staff and hand-delivered letters to all the parents. A Press release was to be released at 9am that morning.

"Not very many people knew but one of them told The Argus."

Mr Miller said the council was looking at ways of strengthening its procedures for both elected members and council staff.

About 465 children will have to be moved to other schools and the 40 staff face redundancy if the college closes in 2005.

A final decision will be made in November and legal decisions on any plans will be made in the spring.