Scotland Yard came under “severe pressure” to curtail searches that uncovered a haul of terrorist bomb-making materials because they were too costly, its former head of special operations discloses today.

Andy Hayman, who was closely involved with the liquid bomb inquiry as assistant commissioner at the Metropolitan Police, said that he had faced demands from Thames Valley Police Authority to stop searching woods in High Wycombe.

The searches of the woodland began in August 2006 after the arrest of the alleged liquid bomb plotters. But one of the most significant finds was not made until three months later when bottles of hydrogen peroxide were discovered.

The material had been hidden by Assad Sarwar, the terror cell's quartermaster, who was followed across the country as he attempted to buy peroxide and other chemicals.

Writing in The Times, Mr Hayman says that the local police authority was concerned at the cost of supplying officers to the Scotland Yard operation. “Thankfully we resisted,” Mr Hayman says. “Some of the most important evidence was discovered only several months after the arrests of the plotters.”

Mr Hayman says that the incident illustrates the need for a radical overhaul of the structure of anti-terrorist policing. The present situation, he argues, is “a mess”.

Scotland Yard's Counter-terrorism Command is dependent on the co-operation of chief constables around the country and a new set of regional anti-terror “hubs” in Leeds, Manchester and Birmingham.

Detectives encounter problems with incompatible IT systems, surveillance and armed response teams of varying capability and overstretched lines of command and control.

Mr Hayman writes: “It means that any anti-terrorism operation is complicated by having to work across many county boundaries, dealing with different chief constables and forces of wildly varying manpower and experience. At its worst, it means that the fight against terror can be hampered by turf wars between forces and the clash of the egos of chief constables.

“It is absurd that such an archaic law enforcement structure is allowed to hinder the fight against modern terrorism.”

Mr Hayman retired from the Met this year after 30 years' police service which included a period as Chief Constable of Norfolk and his spell as head of terror operations at the Yard. He attended the Cabinet's emergency committee meetings during the July 2005 bomb attacks in London and advised ministers on terror strategy.

Mr Hayman's proposed solution to the confused structure of policing is a counter-terror unit based at Scotland Yard with national authority.

“The unit should be given nationwide command and control functions with a proper budget.”

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