Police in London have said they arrested at least five people after Greenpeace activists poured red dye into a pond outside the US embassy in protest against arms sales to Israel, AFP reports.

The campaign group said a dozen activists poured 300 litres of biodegradable dye into the pond outside the embassy in southwest London, using containers bearing the words “Stop Arming Israel”.

However, Greenpeace UK said six people had been arrested, including one of its heads, but the police did not provide the names of those detained.

Greenpeace UK’s co-executive director Will McCallum was arrested on suspicion of conspiracy to cause criminal damage, the group said in a statement.

“These arrests are further proof that the right to protest is under attack in the UK. This protest used biodegradable pond dye that is designed to disperse and wash away naturally,” said co-executive director Areeba Hamid.