By Brad Edwards

CROWN POINT, Ind., (CBS) — Monday, July 16, 2012, will be the day the war hit home for one neighborhood in Crown Point – one home after another after another, to be exact.

When Glen Boren heard the news that his neighbor, 21-year-old Indiana National Guard Spc. Sergio Perez was killed in action in Afghanistan, the Vietnam War veteran put up a flag. So did another neighbor, and yet another.

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“I can’t believe that he’s passed, just can’t believe it,” Boren said.

“We’re going to put a flag in tribute to him,” said neighbor Robert Block.

CBS 2’s Brad Edwards reports Perez and a comrade were killed by enemy fire in Afghanistan. Perez was a 2010 graduate of Lake Central High School.

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According to the Indiana National Guard, Perez and Spc. Nicholas Taylor, from Berne, Ind., were killed during a complex attack, that included rocket propelled grenade fire and small arms fire in Kandahar province, during a bomb clearance patrol on Monday.

“He was the greatest guy I knew, actually,” said his best friend Esteban Gutierrez. “Finding out yesterday was the worst news ever.”

Sgt. Perez was part of the 713th Engineer Company headquartered in Valparaiso. Earlier this year, four other more members of the unit were killed in a single attack.

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“Every such loss is a heartbreak,” said Gov. Mitch Daniels. “No Guard Unit in memory has been assigned a more dangerous mission than the 713th.”

Brad Edwards