The head of Greenpeace UK has been arrested after the group poured blood-red dye into the US embassy’s pond in protest against arms sales to Israel.

The campaign group said it had tipped 300 litres of biodegradable dye into the water outside the building in Nine Elms, south west London.

Will McCallum, Greenpeace UK’s co-executive director, was arrested on suspicion of conspiracy to cause criminal damage, alongside five other activists who also face charges of criminal damage.

If charged and convicted of the offence, he could be jailed for a maximum of 10 years.