A gunman has opened fire on members of Congress practicing for a charity baseball game in Alexandria, Virginia, injuring House of Representatives majority whip Steve Scalise and several members of the congressional police force.

Scalise, a Republican from Louisiana, was shot Wednesday at around 7:30 am by a gunman during a baseball game with several other Republican lawmakers.

Scalise, the third ranking member of House Republican leadership as the majority whip, appeared to have been shot in the hip and it appeared two Capitol Hill police agents were shot, according to Representative Mo Brooks.

Brooks told CNN that at least five people were injured, including two law enforcement officers and a congressional aide.

Brooks described a scene of chaos and of players taking cover wherever they could on the field.

US President Donald Trump announced after the shooting that the gunman, identified by law enforcement as James T. Hodgkinson III, has now died from his injuries.

The alleged shooter was reportedly shot by Capitol Police officers.

We are deeply saddened by this tragedy, he said. Our thoughts and prayers are with the members of Congress, their staffs, Capitol Police, first responders, and all others affected,Trump said earlier in a statement.

About 50 to 100 shots were fired, congressional sources said.

The site includes a park with baseball fields where members of the congressional baseball team regularly practice.

Representative Mike Bishop from Michigan said the gunman was standing outside the fence line behind third base aiming for the field's only exit.

If not for the detail who stepped up with basic revolvers, we would've all been dead, he said, referring to members of the security team. He said he Army-crawled his way to taller grass and tried to reach the dugout, but bullets were hitting the dugout as well.

Images and footage from the scene show bullet holes in windows of buildings around the scene of the shooting.

Alexandria police said in a tweet that the suspect was in custody. It also advised people to stay clear from the area.

The FBI has arrived at the scene of the shooting, which is about 7 miles away from the White House in Washington, DC.

In a statement, Texas Representative Roger Williams, one of the team's coaches, said one of his staff members, legislative correspondent Zack Barth, was shot during the incident and is receiving medical attention. Williams tweeted Barth was receiving medical attention but is doing well and is expected to make a full recovery.