**Iraqi security forces have been deployed en-masse in Baghdad, bringing the capital to a near standstill.**Security officials says the lockdown was imposed after they received intelligence that militants were planning attacks across Baghdad.
Police have blocked off access to some roads and thoroughfares in the city.
Last month a series of car bombs in Baghdad killed more than 120 people. Security has been tightened ahead of a crucial general election in March.
Clampdowns of this sort have become rare in the past two years.
BBC Baghdad correspondent Jim Muir says the police have dismissed rumours that a senior politician had been assassinated and that the clampdown was purely preventative.
Official figures show that violence across the country has fallen in the past 18 months.
But in the past five months Baghdad has been rocked by a series of large suicide bombings near government targets, causing mass casualties.
The Iraqi government has been criticised for its handling of security in the capital. Government officials blame the violence on members of Saddam Hussein’s Baath party, working with al-Qaeda and other militant Sunni Arab groups.
Jim Muir says there is a strong belief that more such attempts will be made with the approach of general election in March.