Feb. 1 (Bloomberg) -- At least 53 people were killed in Baghdad, the worst bloodshed in the Iraqi capital in six months, when devices carried by women exploded at two markets.

Both women had Down syndrome and the bombs that were strapped to them were detonated by remote control, the Associated Press said, citing the Iraqi military. The U.S. blamed al-Qaeda for the bombings.

The attacks underscore ``the absolute bankruptcy and brutality of the enemy of the people of Iraq who would do such a thing,'' U.S. Secretary of State Condoleezza Rice told reporters in Washington today. ``The presence of suicide vests in this way is a very difficult challenge.''

U.S. Ambassador to Iraq Ryan Crocker said the use of the mentally retarded women shows al-Qaeda has ``found a different, deadly way'' to try to jeopardize Iraq's security, AP reported.

The first blast left 45 people dead and 75 hurt at al-Ghazal pet market, President Jalal Talabani's party said on its Web site. The woman involved wasn't Iraqi, Baghdad security forces spokesman Qasim Ata told state television. The second bomb killed eight and wounded 10 at a market in the al-Jadida district, Talabani's Patriotic Union of Kurdistan said. The attacks were 10 minutes apart, the first at 10:40 a.m., the U.S. military said.

`Phantom Phoenix'

The U.S. has channeled resources into fighting in northern Iraq after successes in combating terrorism in the capital. Operation Phantom Phoenix, a U.S.-led campaign to rid Iraq of al- Qaeda fighters and target their weapons caches, began last month. Defense Secretary Robert Gates said on Jan. 10 that al-Qaeda had been largely ``squeezed'' out of Baghdad.

AP said at least 73 people died and more than 100 were wounded in the blasts, while the U.S. military put the toll at 27 dead and 53 wounded.

``Coalition sources believe both events were carried out by al-Qaeda in Iraq,'' the military said in an e-mailed statement, referring to the group's Iraq organization.

``These extremists have no regard for life,'' Gordon Johndroe, a spokesman for the White House National Security Council, said in an e-mailed statement. ``We will continue to stand with the Iraqi people to defeat these terrorists.''

The U.S. military and Iraqi forces have been targeting the northern provinces, particularly Ninewah and its capital, Mosul, where extra troops have been deployed to target al-Qaeda militants who have fled the south.

Clearing and holding Ninewah will be a ``tough fight'' for Iraqi and U.S. forces because al-Qaeda has been pushed north from the provinces of al-Anbar, Diyala and the capital, U.S. Major General Kevin Bergner said Jan. 30.

Prime Minister Nuri al-Maliki announced Jan. 25 a ``final war'' against al-Qaeda in Mosul after two bombings there killed more than 30 people, including the provincial police chief.

Baghdad's Al-Ghazal market was targeted previously on Nov. 23, when 13 people were killed and more than 22 wounded. On Aug. 1, three car bombings in Baghdad killed more than 80 people.

To contact the reporter on this story: Camilla Hall in London at chall24@bloomberg.net.

Last Updated: February 1, 2008 14:42 EST