Blasts heard from Baghdad's Green Zone

Baghdad: Witnesses say a rocket or mortar has been fired into the Green Zone in the Iraqi capital. There was no immediate word on casualties or damage.

Meanwhile, a curfew was imposed on Baghdad and streets were empty of cars and trucks as Iraq marked the fifth anniversary of Baghdad's capture by US forces.

However, fighting continued to plague the city. In the latest attack, black smoke could be seen rising from the fortified Green Zone after a blast was heard.

Loudspeakers warned residents to take cover and await further instructions, while helicopters circled overhead.

The shelling on Wednesday was the latest in a series of attacks on the part of Baghdad that houses the Iraqi government and US Embassy. Two US soldiers died in a similar attack last week.

The attack comes a day after top US commander General David Petraeus called in Washington for an open-ended suspension of US troop withdrawals this summer because of concern over the renewed fighting.