Story highlights At least 16 people are killed in explosions and shooting Tuesday, police say

Analyst: "This takes the cake ... given the scale of the operation, its potential impact"

State-run TV reports that guards at Abu Ghraib were complicit in escapes

Al Qaeda group claims responsibility; at least 500 inmates reportedly escape

An al Qaeda group claimed responsibility Tuesday for coordinated attacks on two Iraqi prisons that a lawmaker said freed more than 500 inmates, including some senior members of the militant group.

Militants supported by suicide bombers and armed with mortars, rocket-propelled grenades and machine guns attacked two Iraqi prisons Sunday and Monday as inmates inside rioted and set fires, ending in a massive jailbreak, authorities said.

The attacks occurred Sunday night at Abu Ghraib, west of Baghdad, and al-Taji prison, north of the capital.

At least 21 inmates and at least eight prison guards were killed, the Iraqi Justice Ministry said, while 25 inmates and 14 guards were wounded.

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The Justice Ministry did not say how many inmates had escaped, but lawmaker Hakim al-Zamili said Monday that more than 500 fighters had gotten away.

A statement posted on radical Islamist websites and purporting to be from the Islamic State of Iraq and the Levant claimed responsibility for the attacks and said that "more than 500 of the best jihadi fighters" were among the freed inmates.

CNN could not confirm the authenticity of the statement, which was signed by the group's Information Ministry instead of the more usual official media wing.

State-run TV Al Iraqiya reported that guards at Abu Ghraib, also known as Baghdad Central Prison, facilitated the prison break. Al Iraqiya ran part of an interview with Prime Minister Nuri al-Maliki, who said "the guards who were present inside the prison were part of this militia, they were complicit, and they are the ones who opened the prison gates."

Al Iraqiya TV also reported that the Ministry of Interior had arrested a number of the escapees, but the report did not specify a number or from which prison they had escaped.

Ramzy Mardini, adjunct fellow at the Beirut-based Iraq Institute for Strategic Studies, compared the attacks to a previous prison break in Yemen. Many of those who escaped then belonged to al Qaeda.

"Like in Yemen in 2006, this could be al Qaeda's so-called great escape moment in Iraq, whereby a prison break is large and significant enough to exhibit noticeable impact on the insurgency and the group's effectiveness for the foreseeable future," Mardini wrote in an e-mail to CNN.

"Al Qaeda has certainly proven its reach over the past year to still exhibit a capacity to pull off high-profile and coordinated attacks. But this takes the cake, especially given the scale of the operation, its potential impact and the fortified nature of the target," he said.

Mardini described the attacks as al Qaeda's "best advertisement" in terms of propaganda since 2009 bombings in Baghdad.

Meanwhile, at least 16 people were killed and dozens wounded in a new wave of explosions and shooting in Baghdad and Mosul on Tuesday, according to police officials.

Three roadside bombs exploded in rapid succession near a popular restaurant in southern Baghdad, killing seven people and wounding 28 others. A car bomb and two roadside bombs outside a Sunni mosque, also in southern Baghdad, killed four people and wounded 15 more, officials said.

In western Mosul, the northern Iraq metropolis, gunmen at a livestock market killed three Shiite people, who police said were visiting from Baghdad. Two prison guards were shot dead in eastern Mosul.

Attacks on Monday also rocked Mosul. A suicide bomber blew himself up at an Iraqi army post in northern Mosul's Kokjili district in the morning, police said. At least 16 people were killed and 21 were wounded. Both civilians and soldiers were among the victims.

Later, at least four people were killed and two were wounded when a roadside bomb exploded near a Sunni mosque in the al-Muthana neighborhood of central Mosul, police said.

The deadly fighting is the latest in a string of violence in recent months, much of it stemming from discord between Sunnis and Shiites. Sunnis have long felt politically marginalized under a Shiite-led government in the post-Saddam Hussein era. They enjoyed more political clout during Hussein's rule before his ouster after the U.S.-led 2003 invasion.