Two of four men arrested in a counter-terrorism operation last weekend have now been released without charge, police said.
Scotland Yard said a 28-year-old British national of Azerbaijani origin arrested last Sunday on upmarket Westbourne Grove in west London had been released without charge.
Earlier, a spokesman confirmed a 29-year-old British national of Pakistani origin arrested in Peckham, south-east London, had also been freed.
Two 25-year-olds are still in custody following a swoop where marksmen used special ammunition to stop a car on Mansell Street, near the Tower of London.
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Nearly 38,000 runners will hope to complete Sunday's London Marathon making it the biggest event in its 35-year history.
Rain across central Britain with longer, intense downpours with thunder in places this evening. A lucky few will stay sunny and dry.
Planning on going to the London Marathon tomorrow? Read our handy guide first!