Bloodshed has increased recently, despite what the military said has been a 60 percent drop in attacks across Iraq since June. Last Thursday, two massive bombs killed 68 people in Baghdad's Karradah neighborhood. On March 3, two car bombings killed 24 people in the capital.

According to an Associated Press count, at the height of unrest from November 2006 to August 2007, on average approximately 65 Iraqis died each day as a result of violence. As conditions improved, the daily death toll steadily declined. It reached its lowest point in more than two years on January 2008, when on average 20 Iraqis died each day.

Those numbers have since jumped. In February, approximately 26 Iraqis died each day as a result of violence, and so far in March, that number is up to 39 daily. These figures reflect the months in which people were found, and not necessarily – in the case of mass graves – the months in which they were killed.

Military spokesman Rear Adm. Gregory Smith said Sunday that recent violence should not be taken as evidence of "an increase or a trend of an increase".

"I think we need to continue to look at historically what has happened over the last year to really put in perspective a one-week or two-weeks' worth of activity inside Baghdad," Smith said.

But Smith, in what has become a military mantra of caution, also noted that "on any given day, al-Qaida and other extremist groups are still very much disposed toward handing out violence indiscriminately to achieve whatever means and ends they hope to achieve with those attacks."

While al-Qaida in Iraq is Sunni, Shiite extremists with alleged ties to Iran are also believed to have carried out attacks.

In an interview with CNN Tuesday, Gen. David Petraeus, the top US commander in Iraq, said he was in favor of substantive discussions with Iran about what the US claims is Tehran's continued funding and training of extremists in Iraq.