Top anti-terror cop steps down amid inquiry

LONDON, England (CNN) -- Britain's top anti-terrorism police officer has resigned his position after media allegations that he faced an investigation into some of his expense claims.

Assistant Commissioner Andy Hayman stepped down in his role as head of the Metropolitan Police's Specialist Operations Directorate, which includes Counter Terrorist Command, according to a statement released by New Scotland Yard, HQ of London's police force.

The UK faced some of its biggest terror threats of recent times during Hayman's period in the post, which he took up in February 2005, including the July 7, 2005 bombings, which killed 52 people and left more than 770 injured on the London mass transit system.

Other terror alerts included the alleged plot to bomb trans-Atlantic airline flights in August 2006; and the attempted terror attacks on Glasgow airport and central London in June of this year.

Hayman was subject to criticism for his role in the aftermath of the shooting of Jean Charles de Menezes, the innocent Brazilian killed by police during the hunt for terror suspects following the aborted attack on London on July 21, 2005.

In a statement Hayman said that in recent weeks there had been a "series of leaks and unfounded accusations" which he said he would continue to refute. Such accusations had impacted his personal life, he added. "It also puts you in the spotlight, often in ways that are very hurtful."

The UK's Press Association and other media organizations have reported that Hayman has been asked to account for at least £15,000 ($31,000) worth of expenses claims.

Hayman continued that "these events take their toll on you personally and I feel now is the right time for me to step aside and for a new person to take over as Assistant Commissioner Specialist Operations and Head of the ACPO Terrorism and Allied Matters (TAM) business area.

"It has been a great honour and privilege to lead Specialist Operations in its challenging work protecting this country from the palpable terrorist threat we face.

Sir Ian Blair, Metropolitan Police Commissioner, who is in charge of the force, said that Hayman could be proud of what he had achieved.

"In this year alone, 37 people have been convicted in terrorist related cases following investigation by the Met. He has also made a significant contribution to the development of policing and the service during his career."

The recruitment process for a successor to Hayman will begin at once, a Scotland Yard spokeswoman said. E-mail to a friend