He saw a psychiatrist last month and showed no "sign of any likely violence either to himself or others," McHugh said.
Suzie Miller, a 71-year-old retired property manager who lived in the same Killeen apartment complex as Lopez, said few people knew him and his wife well because they had just moved in a few weeks ago.
"I'd see him in his uniform heading out to the car every morning," Miller said. "He was friendly to me and a lot of us around here."
Shaneice Banks, a 21-year-old business-management student who lived downstairs from the Lopezes, said her husband, who also works at Fort Hood, helped the couple move in. Hours before the shooting, Banks said she ran in to Lopez when he came home for lunch.
"He was going to his car, and I was like 'Hey, how's your day going?' And he seemed perfectly fine. He was like, 'Day's going pretty good. I'll see you whenever I come back home.'"
When word came out that there was a shooting at the base, Banks saw Lopez's wife frantically calling her husband over and over, trying to reach him via cellphone from the apartment's shared courtyard.
"She was bawling because they have a 2-year-old, and she was just holding the baby," Banks said. "My heart just went out to her. I was trying to get her information when I could but she doesn't speak a lot of English."
Xanderia Morris lives next door to Banks. She also saw Karla Lopez distraught in the courtyard.
"We tried to console her. She called some people over, and we were consoling her, and then she started up the stairs back to his apartment, and they identified him as the shooter on television. She just broke down. We had to rush her up the stairs so nothing would happen to her," Morris said.
Neighbors took Lopez into Morris' apartment, where she sat crying on the sofa for a long time.
The shootings revived memories of the November 2009 shooting at Fort Hood, the deadliest attack on a domestic military installation in U.S. history. Thirteen people were killed and more than 30 were wounded.
Army psychiatrist Nidal Hasan was convicted last year in that assault, which he has said was to protect Islamic insurgents abroad from American aggression.
After that shooting, the military tightened base security nationwide.
In September, a former Navy man opened fire at the Washington Navy Yard, leaving 13 people dead, including the gunman. Defense Secretary Chuck Hagel ordered the Pentagon to review security at all U.S. defense installations worldwide.
Associated Press writers Ramit Plushnick-Masti in Houston; Christopher Sherman in McAllen; Robert Burns, Eric Tucker and Alicia Caldwell in Washington; and Dánica Coto in Guayanilla, Puerto Rico.
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