There's a catch, the officers' rank must be no higher than major and they must pass a background check to make sure their loyalties belong to the new Iraq.
The top ranks of the old army were dominated by Saddam's fellow Sunni Arabs. Some former officers are known to be helping insurgents with planning, tactics and instruction on explosives and weapons.
Tens of thousands of lower-ranking soldiers, mostly Shiites, later found their way back to service when Iraq began to rebuild its army and police forces. It is uncertain how many ex-officers will respond to the call since there was nothing to prevent many of them from joining the new army before.
Word of the recruitment came Wednesday on another violent day in Iraq. A suicide bomber detonated a minibus packed with explosives in an outdoor market packed with shoppers ahead of a Muslim festival, killing about 20 people and wounding more than 60 in a Shiite Muslim town south of Baghdad.
Six U.S. troops were killed, two in a helicopter crash west of the capital.
In other developments:
The suicide bombing occurred about 5 p.m. in the center of Musayyib, a Euphrates River town 40 miles from Baghdad. On July 16, nearly 100 people died in a suicide bombing in front of a Shiite mosque in Musayyib.
Witnesses said the latest attack took place as the market was crowded in advance of the three-day Eid al-Fitr holiday that marks the end of the Islamic holy month of Ramadan. Many women and children were feared among the dead and wounded.
"They want to kill people before the feast," said Nagat Hassoun, 50, who lived a few hundred yards from the blast site. "They want people to stay at home and live in a tragedy. The aim is to cause sabotage. They're targeting the Shiites."
The town police chief, Lt. Col. Ahmed Mijwil, said 22 people were killed and 61 wounded, many in heavily damaged meat and vegetable stalls, shops and cafes. On Thursday, Dr. Ali Abbas, a regional health director, said the wounded included nine children and four women.
"The insurgents wanted to cause as many casualties as possible," said police Capt. Muthanna Khalid.
Elsewhere, fighting flared between U.S. troops and Sunni Arab insurgents in Ramadi, capital of Anbar province 70 miles west of Baghdad. Late Tuesday, a U.S. Marine and sailor were killed when a roadside bomb exploded near their vehicle in Ramadi.
Sporadic clashes occurred throughout the night and into Wednesday, residents said. Associated Press Television News video from the city showed a burning civilian vehicle and what appeared to be a destroyed U.S. Humvee.
A crowd of Iraqis gathered at the site, and one man, waving the remnants of a damaged U.S. M-16 rifle in the air, claimed the attacks caused U.S. casualties.