Steve Scalise, the third highest-ranking Republican in the House of Representatives, was among a number of people shot at a baseball practice in Alexandria, Va., involving Republican politicians and officials.
Congressman Mo Brooks, from Alabama, said it appeared his Louisiana colleague was shot in the upper body.
Brooks said several other people, including two law enforcement officers, also were shot at the practice for a charity softball game Thursday..
Michigan Congressman Mike Bishop said Scalise was standing on second base when gunfire erupted.
“I was looking right at him,” Bishop told Detroit radio station WWJ. “He was a sitting duck.”
Police in Alexandria say a suspect is in custody.
President Donald Trump said in a statement that he and Vice-President Mike Pence were “deeply saddened by this tragedy,” and send their thoughts and prayers to the victims and first responders.
Rand Paul, a Republican and former presidential candidate, was also at the practice.
He told MSNBC he heard a shot, followed by a pause and a “rapid succession of shots” that appeared to be coming from the third-base side of the diamond.
Scalise was elected in 2008 and named majority whip for the Republicans in the House of Representatives in 2014.
Just after his appointment, he dealt with controversy in late 2014 surrounding his appearance as a speaker at a 2002 event in New Orleans.
Scalise said he was unaware the hosts, from the European-American Unity and Rights Organization (EURO), were white nationalists.
It is the second shooting in six years involving a member of the House of Representatives.
Gabrielle Giffords, a Democrat from Arizona, suffered brain injuries when she was shot outside a supermarket. Giffords has since made a remarkable recovery from the shooting, in which six were killed.
UPDATE: Suspect is in custody and not a threat. PIO will be onscene shortly to share updates.