Not enough police officers are joining the new agency

The Serious Organised Crime Agency (Soca) is looking for 1,000 members of the police to join its staff of 4,500.

Its director general, Bill Hughes, told the BBC there is a "reluctance" by some officers to leave established units.

But he said Soca was necessary as the "battle" against organised crime was not being won.

Organised crime, which includes areas such as drug trafficking, credit card fraud and people smuggling, is worth �40bn a year.

Soca, which comes into operation next April, will replace the police's National Crime Squad, the National Criminal Intelligence Service and Customs and Immigration investigation units.

Comfort factor

The BBC's home affairs correspondent Margaret Gilmore says the formation of the agency shows a "genuine desire for radical new approach" to tackling organised crime but its success is not guaranteed.

Mr Hughes, former head of the National Crime Squad, said he can understand why some potential recruits from the police force may not want to join the new agency.

"There is an issue there. There's no denying it. It's a comfort factor," he said.

"They are coming from agencies they understand, that are established, and they are very proud of. "

Mr Hughes said Soca will follow the FBI's lead in pursuing alternative charges against suspected gangs when the evidence of their major crimes can not be proved.

"In the United Kingdom we don't know much about organised crime, we don't know enough," he said.