The Illinois man who in June opened fire on Republican members of Congress at a baseball practice in Alexandria had "cased the field' for weeks and was spotted watching the lawmakers play the day before the shooting spree, according to new report issued Friday.

Authorities said they believe James T. Hodgkinson selected Eugene Simpson Stadium Park as a target as early as April, when took pictures of the field which were later found on his phone. That was shortly after he had driven to Alexandria in a white Ford conversion van, which he lived out of for months.

These details and others are contained in a 41-page report by Alexandria Commonwealth's Attorney Bryan L. Porter, who concluded that U.S. Capitol and Alexandria police officers were "legally justified" in fatally shooting Hodgkinson after the gunman had wounded four people, including House Majority Whip Steve Scalise, and engaged officers in an intense gun battle at a storage shed near home plate.

The report says Hodgkinson fired 62 rounds from the assault rifle — 33 near third base, where he had started his attack, and another 29 near the shed. He fired additional rounds from the handgun. Officers fired at least 40 rounds at Hodgkinson, striking him three times. The incident lasted nine minutes.

Hodgkinson, a 66-year-old unemployed home inspector, had been angry with President Trump, and police have said he deliberately targeted Republicans the morning of June 14. He used a Century Arms International SKS semiautomatic assault rifle and a Smith & Wesson 9mm handgun, authorities said. He had no criminal record, and the guns were purchased legally at two gun shops in Illinois.

Scalise was shot in the hip and gravely wounded as he fielded balls at second base, but recovered. The 51-year-old Louisiana Republican returned to the House for the first time on Sept. 28. Others injured included Matthew Mika, a lobbyist struck in the chest, and Zachary W. Barth, who worked for a Texas congressman and was shot in the left lower leg.

The report credits Scalise's security detail, Capitol police agents Crystal Griner, who was shot in the leg in the first exchanges with the gunman, and David Bailey, with pinning down Hodgkinson with gunfire moments after he started shooting. Bailey, the report says, ran onto the field as Hodgkinson fired through a chain link fence, an action Porter described as a "courageous act" that "helped avert disaster."

Griner and Bailey arrived at the field with Scalise about 6:20 a.m., and then parked the black Chevrolet Suburban SUV 20 feet behind the first base entrance to the field, giving them an unblocked view of the park. They were in the vehicle with the windows down when the first shots were heard just after 7 a.m. Both exited and spotted Hodgkinson at the third-base fence, the rifle barrel sticking through the chain links.

Players were shouting and running; others dropped to the field or dove into dugouts. Scalise was the first to be struck. Mika went down next and was helped off the field. Barth, who was in center field, ran to the warning track but could not find a way out. He lay down and "sensed bullets impacting the ground around him," the report says. He was shot in the leg and ran to the first base dugout.

Bailey saw Scalise fall and tried to run to him but was met by gunfire. The report says he heard "bullets go past his head." Standing by the first base dugout, Bailey returned fire with his Glock pistol, squeezing off 10 rounds across the expanse of the field.

The report says Hodgkinson appeared to lose focus and fired more erratically. He also moved, ducking behind the third base dugout and making his way behind home plate to a blue cinder-block storage shed adorned with a high school logo.

Griner was still at the Chevrolet Suburban, taking cover behind the front driver-side door. Bailey returned to the vehicle to reload his weapon as Griner shot at the gunman. Both agents exchanged gunfire with Hodgkinson. One bullet struck Griner in the left ankle that had become exposed. She could not longer stand, though the report says she continued to fire at Hodgkinson as she lay under the Suburban.