article_snippet.sent: A guard apparently approached The suspect's vehicle and saw two people arguing.
article_snippet.sent: A guard was then shot at least once in the upper body, said Prince George's County Fire Department spokesman Mark Brady.
article_snippet.sent: A guard was in extremely critical condition, according to Prince George's County Fire Department spokesman Mark Brady.
article_snippet.sent: An officer and The suspect were wounded, according to The police chief.
article_snippet.sent: Both were conscious and talking when Both left the scene.
highlights_snippet.sent: A Census Bureau guard is in critical condition, a fire official says .