British police have arrested five men on suspicion of explosives and terror offences near a UK airbase. The arrests followed a tip-off about three suspicious vehicles on Saturday.

The men are held on suspicion of preparing a terrorist act under Section 5 of the Terrorism Act 2006. UK terror law allows suspects to be held for up to 14 days.

US President Donald Trump said the suspects were looking to do big damage. He said they had been under watch by British and American agencies. The White House did not give more details.

British media, including the BBC, the Guardian and the Telegraph, reported that the operation was not intelligence-led. They said alert local residents raised the alarm.

A source familiar with the probe said an Iranian-linked motive looks most likely. Russian sabotage and Islamist motives are also being checked.

Police set up a 400-metre cordon around the site. Bomb disposal teams were called in. Eighty-five homes in the nearby village of Whelford were evacuated. Prime Minister Andy Burnham is being briefed.