It is about time! They should have done this months ago:

The Iraqi commander of the Baghdad security crackdown announced Tuesday that Iraq will close its borders with Syria and Iran for 72 hours as part of the drive to end the violence that has threatened to divide the capital along sectarian lines.
[…]
The general did not say when the borders would close, but another official said it was expected within two days. The official, who spoke on condition of anonymity because he was not authorized to speak to journalists, added that the borders would only partly reopen after the 72-hour closing.
[…]
Gambar, a Shiite and a veteran of the 1991 Gulf War when he served in Saddam Hussein’s army, said security forces also plan to monitor mail, parcels, telegrams and wireless communication devices during the operation.
He said security forces would try to avoid intruding in places of worship, but added that they would do so in “cases of extreme emergencies when it is feared that these places pose a threat to the lives of citizens or if they are used for unlawful purposes.” U.S. and Iraqi authorities have often said Sunni Arab insurgents use mosques to store arms or fire at troops.

I wonder why they just don’t shut the border down until they get the situation under control.