MI5 spied on Nye Bevan for more than 20 years, newly released files show

Britain's domestic security service MI5 kept NHS founder Aneurin "Nye" Bevan under surveillance for more than 20 years, according to newly released files deposited with the National Archives.

The papers show Bevan, the Labour politician from Tredegar, Blaenau Gwent, first came to MI5's attention in the 1930s, when he was considered a left-wing firebrand. MI5 opened a file on him in 1939, while he was the backbench Labour MP for Ebbw Vale. One of the earliest reports described an anti-Nazi rally in Montreal, Canada, that Bevan had addressed.

The monitoring continued after the war, when Bevan served as health minister in Clement Attlee's Labour government. In 1943, Roger Hollis - later MI5 director general - summarised the service's knowledge of him, noting that a decade earlier Bevan had been "in close touch" with the general secretary of the Communist Party of Great Britain.

The files contain no indication that MI5 tapped Bevan's phone or intercepted his mail, and some inside the service questioned why it was watching him at all, since he said the same things in Parliament.

In 1949 the service grew alarmed about Bevan's friendship with Wilfred Macartney, whom it suspected of passing on information obtained from Bevan to the Communist Party. That May, MI5 chief Sir Percy Sillitoe took the evidence to Attlee, who dismissed Macartney's claims.

One of the last reports dates from 1954, when Bevan - back in opposition - met a Russian contact in an encounter that "went off very badly". The file was not closed until 1975, fifteen years after Bevan's death in 1960. One officer later described its contents as "remarkably tame".