POLICE destroyed files relating to anti-war campaigners, unions and several individuals ahead of the undercover policing inquiry, it was heard today. 

The Metropolitan Police Special Demonstration Squad (SDS) spied on campaigners for decades.

A public inquiry was set up when it was revealed that the SDS spied on the family of murdered teenager Stephen Lawrence.

It has already heard testimony from victims of the SpyCops, including women activists with whom undercover police officers had relationships with and fathered children without revealing their true identity.

The interim report found the SDS should have been wound up almost as soon as it was established in the 1970s.

The new revelation, released by the inquiry today, shows that the Metropolitan Police deliberately destroyed secret files before they could be seen by the inquiry.

These included reports on the Stop the War Coalition, the Campaign for Nuclear Disarmament, the Fire Brigades Union, the National Union of Mineworkers, the building union Ucatt, the Jean Charles de Menezes campaign, as well as former MP Dave Nellist and top KC Mike Mansfield.

Stop the War national officer John Rees said: “No-one knows how much information was destroyed and so the inquiry’s contention that most of it will be in other files to which it has access is simply unprovable.

“Even the Metropolitan Police had to admit to the inquiry that it was a ‘significant failure’ to destroy the files without allowing the inquiry to access them first, and without telling the inquiry that the files were being destroyed.”

Deputy Assistant Commissioner Jon Savell said: “The process of reviewing millions of paper documents and classified materials was complex and it was undertaken with care to ensure potentially relevant files were preserved.

“Regrettably, during this process a small number of files which could have been relevant to the ongoing inquiry were destroyed in error, with extensive efforts made to recover them.

“We apologise for this error and take our responsibilities in the preservation of documents for the inquiry very seriously. Robust measures have been put in place to ensure this doesn’t happen again.

“So far, the Met has disclosed 743,000 files to the inquiry, and we continue to fully co-operate with the inquiry as it progresses.”

The inquiry also heard from spy cop Bob Lambert MBE, who faced questions on Mark Jenner’s intimate relationship with activist Allison Smith while undercover. 

Mr Jenner began living with Ms Smith after notifying three unnamed officers of his plan. 

Mr Lambert insisted he did not know about the living arrangements, but was able to write a file note on the move, documented in the inquiry. 

The file noted that Mr Lambert told Mr Jenner that he was not the first undercover officer to conclude that living with an activist was a good idea.

Mr Lambert also faced questions on spy cop Jim Boyling, who infiltrated campaign group Reclaim the Streets and had three sexual relationships during his deployment. 

He denied that he was approached for advice on the topic.