OAK RIDGE, Tenn. (AP) -- Five protesters were arrested Saturday at the Y-12 nuclear weapons plant during a demonstration marking the anniversary of the atomic bombing of Hiroshima, Japan.

The five were arrested on charges of obstructing a roadway at the entrance of the plant in Oak Ridge, where much of the work was done for the World War II-era Manhattan Project.

About 200 protesters were at the plant, and the Oak Ridge Peace Alliance has several other events planned throughout the week for Monday's 62nd anniversary of the bombing of Hiroshima and the Aug. 9 anniversary of the atomic bombing of Nagasaki, Japan. The group has organized annual protests at the Y-12 plant for nearly 20 years.

Arrested were Mary Dennis Lentsch, 70, of Oak Ridge; Elizabeth Velkey Brockman, 44, of Durham, N.C.; Mary Ellen Gondeck, 66, of Detroit; William Hickey, 62, of Detroit; and Billie Hickey, 58, of Detroit.

Oak Ridge Police Capt. Alan Massengill said four of the protesters may face additional charges for chaining themselves with a bicycle chain to a barricade in front of the plant.

Gondeck, a Catholic nun, was released on her own recognizance, but the other four were taken into custody, said Ralph Hutchison, a coordinator with the alliance.

"Things went smoothly. Our goal is to have a nonviolent event celebrating the spirit of peace," Hutchison said.

Protesters walked to the plant from a city park, where they listened to speakers and watched a giant puppet performance. Along the way, activists scattered sunflower seeds as a symbol for nuclear abolition.

© 2007 The Associated Press.