Anti-war campaigners have broken into a military base and occupied tanks bound for Iraq, the Ministry of Defence has confirmed.

Fourteen members of Greenpeace entered Marchwood military port in Southampton on Tuesday morning, one group cutting its way through a fence.

A second group sailed into the port in two rigid inflatable boats, launched from the pressure group's flagship Rainbow Warrior.

Five people are locked inside tanks, while two are chained to the outside of the vehicles, according to Greenpeace.

We are a peaceful protest occupying these tanks for as long as possible to prevent them leaving for Iraq Laura Yates, protester

A further seven protesters have been removed by police.

Ministry of Defence spokesman Richard Whalley said: "We are currently waiting for police with cutting equipment to arrive."

He confirmed at least four people had been arrested and that a hole had been discovered in the perimeter fence.

Protester Ben Stuart said: "We snipped our way through the perimeter fence."

Another protester Laura Yates, who has locked herself inside a tank, said the campaigners have targeted vehicles in a queue on the quayside.

She said: "The police have removed some of us from the outside of the vehicles but now the others are inside. It's going to take quite a long time for them to get us out.

"We are a peaceful protest occupying these tanks for as long as possible to prevent them leaving for Iraq."

Greenpeace last week delayed the military supply ship MV Lyra J from sailing for the Gulf when protesters chained itself to the ship's hull.