By Dominic Casciani BBC News Online

State surveillance: The birth of covert photography Enlarge Image

Photos uncovered by the National Archives show how the police spied on the suffragettes. These covert images - perhaps the UK's first spy pictures - have gone on display to mark the centenary of the votes-for-women movement.

Ninety years ago, a Scotland Yard detective submitted an unusual equipment request.

It was passed up the chain, scrutinised, reviewed and finally rubber-stamped in Whitehall itself. Scotland Yard duly became the proud owner of a Ross Telecentric camera lens. And at a cost to the taxpayer of £7, 6s and 11d, secret police photographic surveillance (in the shape of an 11-inch long lens) was born.

Within weeks, the police were using it against what the government then regarded as the biggest threat to the British Empire: the suffragettes.

Documents uncovered at the National Archives reveal that the votes-for-women movement probably became the first "terrorist" organisation subjected to secret surveillance photography in the UK, if not the world.

The covert photographs are at the heart of an exhibition marking the centenary of the founding of the Women's Social and Political Union, which invented modern direct action and ultimately changed the face of the UK.

State surveillance

The state's use of cameras in fighting crime began when prisons were instructed to photograph all inmates in 1871.

Surveillance pictures revealed: How the police kept watch In pictures

But police found the technology's real value as they tried to combat the increasingly militant suffragettes.

Within two years of the founding of the WSPU, Christabel Pankhurst had become the first woman to be jailed for direct action. That civil disobedience continued within prison walls as jailed women refused to be photographed.

So Scotland Yard brought in the UK's first long-lens paparazzi-style photographer, says Carole Tulloch, curator of the exhibition.

That first photographer, Mr A Barrett, sat quietly in a van, snapping away as the women walked around Holloway Prison's yards, according to the documents.

On the outside, detectives compiled photographic lists of key suspects, the aim being to stop arson attacks, window-smashings or the dramatic scenes of women chaining themselves to Parliament's railings.

KEY DATES 1903: WSPU founded 1905: First jailing 1913: Emily Davison trampled to death by King's horse 1918: Votes for women over 30 1928: Universal franchise

"The police got quite good. They would even send people along to meetings to take pictures and notes of what was being said," says Ms Tulloch.

"They eventually put an officer in plain clothes and on a motorbike to try and keep up. He was able to make some notes but failed to keep up with the suffragettes because he had not been given a bike with an automatic starter motor."

At Manchester Prison, the authorities used the technique to snap infamous window-smashers Evelyn Manesta and Lillian Forrester.

When the results were disappointing, the records suggest another attempt was made to coerce the women into posing.

Evelyn Manesta resisted and eventually a guard was used to restrain her around the neck. But when the photograph was reproduced in the official rogue's gallery, it had been doctored - replacing the arm with a fashionable lady's scarf.

Gallery panic

Back in London, the nation's greatest art collections were nervous after suffragettes slashed the National Gallery's Rokeby Venus in March 1914.

SUFFRAGETTES' LEGACY We still have her suffragette plaque and brooch and I remember as a child how my mother and grandmother would bring them out and explain to me their significance Annette Ure History of the suffragettes

The private Wallace Collection gallery appealed to Scotland Yard for help, and detectives supplied their list of London's most wanted - almost all of the pictures secretly taken.

One of the women on the list, Kitty Marion, went on to become one of the most celebrated of the suffragettes as she endured more than 200 force-feedings in prison while on hunger strike.

"On the one hand, the state considered them dangerous terrorists, but on the other it simply did not know what to do with them," says Ms Tulloch.

"The police and prison officials were so worried about what to do they made sure that every step they took was authorised by the Home Office. In the records you can find daily communications between the governor of Holloway Prison and Whitehall. In that era it was extremely rare for government to communicate so quickly."

But the police surveillance did nothing to stop the movement - nor did it dim the growing support they were finding in the country.

While the photographs presented the women as dangerous subversives, press photographs uncovered by the National Archives also exposed what some newspapers - particularly the Daily Mirror - regarded as police and mob brutality.

"I think we take for granted what they fought for," says Ms Tulloch. "One of the images we found shows a lone woman on a cart, surrounded by 1,000 men.

"Today, she would be on a podium, surrounded by supporters in an organised event. No doubt many of those men would be telling her what to do - go home and feed the kids. The courage these women showed was remarkable."

The March of the Women exhibition at the National Archives in Kew, Richmond, Surrey, and is free. It will be open from Monday, 6 October until 31 December.