BAGHDAD, Jan 9: Two suicide bombers disguised as senior police officers blew themselves up inside a ministry compound on Monday, killing 28 people in an attack that raises further questions about Iraqi government’s stability.

Al Qaeda in Iraq claimed responsibility for the attack, which left 25 people injured.

The two suicide bombers managed to get inside the interior ministry compound in Baghdad, as senior dignitaries, including the US ambassador to Iraq, were at a nearby parade to mark National Police Day.

One was wearing the uniform of an Iraqi police major while the other was dressed as a lieutenant-colonel. Both had high-level security passes which enabled them to get through the main checkpoint to the compound, and would have allowed them to get into the ministry itself.

“We’re dying to know how they got hold of these badges to enter the building,” one police source said. “This is a disaster. We can’t understand how they managed to get inside without being searched.”

Once inside the checkpoint, interior ministry guards became suspicious of one of the attackers because of his bulk, and shot at him, detonating his explosive belt. The second bomber then blew himself up, causing more carnage.

Al Qaeda in Iraq claimed responsibility for the attack, which left 25 people injured.

US military spokesman Lt Col Barry Johnson, who was at the nearby ceremony, said ambassador Zalmay Khalilzad was unhurt and the parade continued as planned.

AL QAEDA’S CLAIM: In its statement the Al Qaeda in Iraq said: “Two brothers ... got through nine checkpoints that the infidels set up around the building, then one of them piled into dozens of ministry officers,” said the statement posted on a Web site generally used by militants.