The shooting occurred at approximately 10:50 a.m. at 801 G St. NW, MPD spokesman Araz Alali told the Alley.
"He is conscious and breathing, was transported to a local hospital and the suspect was apprehended," Alali said.
The FBI is investigating the incident, as it took place in a federal building, he added. An FBI spokeswoman told the Alley that the agency is interviewing the suspect.
FRC President Tony Perkins released a statement, saying "The police are investigating this incident. Our first concern is with our colleague who was shot today. Our concern is for him and his family," he said.
FRC is a Christian, conservative advocacy group that has been very vocal against same-sex marriage.
Lawmakers and candidates have issued statements about the incident in the hours following the shooting.
Republican presidential candidate Mitt Romney released a statement, saying he was "appalled" by the shooting. "There is no place for such violence in our society. My prayers go out to the wounded security guard and his family, as well as all the people at the Family Research Council whose sense of security has been shattered by today's horrific events," Romney said.
House Speaker John Boehner tweeted that prayers are with the injured guard and his family. Rep. Louie Gohmert, R-Texas, tweeted that "My thoughts and prayers are with our Christian brothers and sisters at The Family Research Council."
This post has been updated. Originally published 11:58 a.m.
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