Police shot and killed at least five people Sunday after gunmen opened fire on a group of contractors traveling across a bridge on their way to make repairs, authorities said.

Deputy Police Chief W.J. Riley said police shot at eight people carrying guns, killing five or six.

Fourteen contractors were traveling across the Danziger Bridge (search) under police escort when they came under fire, said John Hall, a spokesman for the Army Corps of Engineers (search).

They were on their way to launch barges into Lake Pontchartrain (search) to help plug the breech in the 17th Street Canal, Hall said.

None of the contractors was injured, Mike Rogers, a disaster relief coordinator with the Army Corps of Engineers, told reporters in Baton Rouge.

The bridge spans a canal connecting Lake Pontchartrain and the Mississippi River.

No other details were immediately available.