The suspect is in custody and no longer a threat, according to Alexandria police.
Paul and Rep. Mo Brooks, R-Ala., described the weapon used by the shooter as a rifle. Paul said he heard a first, “isolated” shot followed by a “rapid succession” of 5 to 10 shots.
Brooks told CNN that he saw Scalise pull himself from second base into the outfield after he was shot, leaving a trail of blood 10 to 15 yards long.
In a statement, President Donald Trump said that he and Vice President Mike Pence are “monitoring developments closely.”
“We are deeply saddened by this tragedy. Our thoughts and prayers are with the members of Congress, their staffs, Capitol Police, first responders and all others affected,” Trump said in a statement.
This story is developing. Please check back for further updates.
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— CNBC’s Katie Little contributed to this report