The two, who were not identified until their families are told, died Saturday "of wounds suffered when enemy forces attacked their unit with indirect fire," the Pentagon statement said.
Meanwhile, Iraq's Al Sumaria TV channel reported that 247 Iraqis were killed in violence during March.
The victims included 136 civilians, 56 soldiers and 55 policemen, the Health, Defense and Interior ministries said, while 215 civilians and 155 security personnel were wounded.
In the same period, 72 "terrorists" were killed and 209 arrested, the Iraqi government said.
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