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Just hours after an explosion killed seven Marines in his home state, Nevada Sen. Harry Reid used the fatal training accident as an opportunity to talk about the potential impact of the sequester on military readiness.

The Senate Democratic leader initially took to the floor Tuesday to mourn the deaths of the seven Marines, killed during a training exercise at Hawthorne Army Depot in Nevada.

"My thoughts are with those who are injured and of course the families of those who lost loved ones," Reid said.

But then, after explaining that the Marines were at the depot for training, Reid went on to use the tragedy as a segue to talk about the importance of canceling the automatic budget cuts known as sequester.

"It's just not appropriate, Mr. President, that our military can't train and do the maintenance necessary," Reid said. "These men and women, our Marines, were training there in Hawthorne and with the sequester it's going to cut this stuff back, and I just hope everyone understands sacrifices made by our military, they are significant."

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    While using the activities at the Nevada facility as an example of critical training that would be cut, Reid did not appear to directly link the budget cuts to the deaths.

    Still, some took offense at his comments.

    "I don't know how anyone could link this accident to budget cuts. Budget cuts would never cause Marines to operate in unsafe conditions," one Marine official told Fox News.

    Reid urged Congress to pass a bill allowing the military flexibility to move around money and spare certain parts of the budget. His office later sought to clarify his reference to the deadly explosion.

    "In the wake of the Hawthorne tragedy, Senator Reid's thoughts are with the Marines who were killed or injured and their loved ones," spokeswoman Kristen Orthman said. "The idea that Senator Reid thinks the Hawthorne tragedy has anything to do with the sequester is absurd and unsubstantiated by his remarks on the topic. Marines would not be forced to operate under unsafe conditions due to budget cuts."

    A senior Pentagon official adds: "Reid didn't directly tie sequestration and the tragedy at Hawthorne. He made a general point about how training and readiness will suffer if sequestration isn't lifted."

    The cause of the explosion is still under investigation by the Marines. But military officials confirm that a 60-millimeter mortar round exploded prematurely inside its tube at about 10 p.m. local time Monday. This was a nighttime live fire exercise carried out at an Army ammunition depot.

    Seven Marines from North Carolina's Camp Lejeune from the 2nd Marine Division were killed -- three of them immediately.

    The others died while waiting to be transported to nearby hospitals. Some of the wounded were taken to Reno.

    The Hawthorne Army Depot has been used since 1930. It is 230 square miles and has nearly 3,000 buildings.