In Phoenix, Arizona, Mitt Romney continued the line of attacks on Rick Santorum that he began at a debate in Mesa. NPR's Ari Shapiro reports Santorum is threatening to beat Romney during Tuesday's primaries in Michigan and Arizona.

 

Rick Santorum has built his campaign on a reputation for uncompromising conservatism. Mitt Romney is trying to show that Santorum compromised his conservatism repeatedly as a senator from Pennsylvania.

 

“Explain most of the night why he did or voted for things he disagreed with. And he talked about this as being taking one for the team. I want to know which team he was taking it for.”

 

The Mesa debate could be the last one of this primary season. More than a dozen states will vote in the coming weeks, and the candidates have not signed on to any more debates after that. Ari Shapiro, NPR News, Phoenix, Arizona.

 

An investigation is underway into a helicopter collision that has killed seven Marines. The service members were taking part in a training mission last night when the choppers collided near Yuma, Arizona.

 

The Taliban are urging the Afghan people to attack US bases in retaliation for Koran burnings at a NATO military base. The insurgent group is also calling on security forces to kill Westerners. President Obama has apologized to Afghan President Hamid Karzai, saying the burnings were unintentional. But the incident continues to fuel protests for a third straight day.

 

Russian Prime Minister Vladimir Putin spoke today before tens of thousands of people at a rally in Moscow. NPR's Corey Flintoff reports that the gathering appears to be a response to the mass opposition rallies that have shaken the government.

 

Putin is running for president in the March 4th elections, and there’s little doubt that he’ll win. But these huge gatherings appear to be an effort to add legitimacy to his victory. He told the rally that he has always helped Russia to win and asked them will we win now? The answer from the crowd was a resounding ‘yes’. Many people at the rally came in organized groups of government employees, such as social workers and teachers. Some said they were there at the beating of their employers. Some demonstrators were brought in from other parts of Russia, and they declined to say who was paying for their trips. Corey Flintoff, NPR News, Moscow.

 

At last check on Wall Street, the Dow was up 31 points at 12,970.

 

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Today, more evidence of improving job market in the US. The Labor Department says there’s been no increase in the number of people who file for unemployment insurance. The figure remained flat at 351,000 last week, and a less volatile four-week average has fallen again to its lowest level in four years.

 

State investigators in West Virginia have reached the same conclusion as three other investigations into the 2010 coal mine disaster that killed 29 mineworkers. But NPR's Howard Berkes says the state report points to shortcomings in West Virginia law.

 

The report from West Virginia's mine safety agency is the fourth investigative review of the Upper Big Branch mine explosion. State investigators largely agree with the earlier federal union and independent reports, hinting the explosion on uncontrolled methane gas, excessive coal dust, faulty safety systems and management failures. But the report's tone is tepid compared to the strong language in the earlier reports. It does know that no one higher than a mine foreman can be held responsible under state law. A bill permitting sanctions against higher-ranking company officials has stalled in the West Virginia's legislature in the face of industry opposition. Howard Berkes, NPR News.

 

Argentina is observing two days of mourning for the victims of yesterday's train crash in Buenos Aires . It was the worst the country had experienced in decades. At least 50 people are confirmed dead; hundreds more remain hospitalized. Officials say they are investigating why a commuter train operating during morning rush hour slammed into the buffers at a downtown station in Buenos Aires.

 

US stocks continue to show gains with the Dow up 30 points at last glance; it's at 12,968.

 

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