More than 60 police officers and soldiers have been detained over twin suicide bombings that killed at least 155 people in Baghdad on Sunday, Iraqi authorities have said.

Iraqi military officials announced the arrests on Thursday, saying that 13 senior officials were among those detained.

The arrested men were deployed in the Salhiya section of Baghdad, where the bombings targeted the justice ministry and Baghdad provincial council, General Qasim Atta, an army spokesman, told the AFP news agency.

"The commission of inquiry into the double attacks on Sunday ordered the arrest of 13 officers of various ranks, and 50 members of the security forces responsible for the protection of Salhiyeh," he said.

It was not immediately clear if those detained were suspected of involvement in the bombings or negligence in carrying out their duties of protecting the capital.

Responsibility

Ali al-Dabbagh, an Iraqi government spokesman, denied that the security personnel had been formally arrested.

"First, their cases have to be investigated and we have to hold them accountable for any lack of duties which we need to have in order to make them completely ready and to show them the full responsibility of those security forces," he told Al Jazeera.

"As you know, we are coming close to elections and those groups that intend to destroy the Iraqi political process and don't want this new system in place.

"Plus, al-Qaeda is part of their ideology which also wants to destroy the current Iraqi political system. In the end this isn't a challenge just for the government, but for all of Iraq and its people, so we had no choice but to arrest them."

Salah Abdul Razzaq, Baghdad's governor, has blamed negligence or even collusion by the security forces for the bombings, and has called for Jawad al-Bolani, the interior minister, and Lieutenant General Abboud Qanbar,the Baghdad Operations Command chief, to  be sacked.

The commanders of 15 checkpoints in Salhiyeh were also among the security personnel arrested.

Iraqi fears

The attacks were the deadliest in Iraq in two years, targeting government buildings and raising fears about Iraq's ability to protect itself as it prepares for the US military withdrawal.

The Iraqi government blamed them, and earlier bombings on August 19 that devastated the foreign and finance ministries, on al-Qaeda and supporters of Saddam Hussein's outlawed Baath party.

Iraq's foreign minister has called for a UN inquiry into Sunday's blasts, which left hundreds of other people injured.

Hoshiyar Zebari said the inquiry should focus on the support given by foreign countries to fighters.

He said the attacks reinforced the need for international support to help his country defend itself.

Zebari's call came amid growing public anger in the wake of the bombings, which occurred close to the heavily-fortified Green Zone.

Some Iraqis have accused the government of a major security breach that saw the two suicide truck bombers penetrate what was supposed to be one of the safest areas in the capital.