A group of anti-nuclear protesters who chained themselves together have been arrested for public order offences outside a Rolls-Royce plant in Derby.
The protest lasted about six hours
About 40 campaigners are staging demonstrations at the factory to oppose the use of nuclear materials at the firm's Raynesway site.
A rally organiser said 10 activists were arrested on Monday morning.
Derbyshire Police spokesman James Allen said dozens of officers are in the area to prevent any problems.
The protesters said nuclear fuel rods produced at the factory are used in the UK's Trident nuclear weapons system.
Campaigner Zina Zelter said: "If Rolls Royce refused to make the nuclear reactors for Britain's nuclear weapons system Trident, then Britain would be unable to threaten the world with its nuclear weapons."
She called on Rolls Royce to produce an emergency evacuation plan for people living and working within a two-mile radius of the factory.
CND spokesman Tom Cuthbert, who was at the protest, said: "We are very glad the protest did pass off peacefully.
"To have this sort of material and activity so close to a city centre is asking for trouble."
He said the arrests were probably made after demonstrators strayed off a designated assembly area set for them by police.
In a statement, Rolls Royce officials said: "Our Raynesway facility operates within strict guidelines set by the Environment Agency, Nuclear Installations Inspectorate (NII) and Health and Safety Executive.
"Its emergency procedures are regularly reviewed by the NII, which has accepted Rolls-Royce findings that there is no reasonably foreseeable off-site hazard."