Trans killer dad Robert Dorgan said nothing before calmly shooting dead his son and ex-wife and pumping bullets into her parents at a high-school hockey game in Rhode Island, officials revealed Tuesday.

The event was supposed to be extra special for the athletes and their families: It was the high-school team’s “senior night,” where its 2026 graduating students would be feted and their relatives asked to join them on the ice for a special ceremony.

“There was no indication that there was going to be violence. This individual had gone to many hockey games in the past,” Pawtucket Police Chief Tina Goncalves told reporters, calling the brutal attack “a domestic violence incident.”

Goncalves said Dorgan, 56, who was transgender, was armed with a Glock 10mm and a SIG Sauer P226 at the time of the “very targeted attack” at the Dennis M. Lynch Arena on Monday afternoon.

“To have virtually a complete family shot and several killed, I just can’t imagine what those families are going through,” said Rhode Island Gov. Daniel McKee on Tuesday.

Authorities said the killer’s exact motive was still unknown, although he clearly harbored a deadly resentment against his family.

Surveillance footage from the arena showed Dorgan — who was wearing women’s clothing — enter and exit once before he returned to the arena and started shooting.

Goncalves said Dorgan was there “for quite some time” before the attack but claimed nothing about his presence was unusual before the bloodshed.

Three good Samaritans were eventually able to overcome Dorgan once he started shooting, the cop said.

The suspect then produced a second firearm and shot himself dead.

Pawtucket Mayor Donald Grebien commended the individuals who wrestled with the madman, saying their selfless bravery “saved lives.”

Dorgan’s guns were both obtained legally, and he had a license to carry a concealed weapon in Florida, authorities said. It was not immediately known whether he had a license to carry outside of the Sunshine State.

His ex-wife Rhonda, 52, and their son Aidan Dorgan, 23, were both killed in the heartless attack.

Goncalves identified the three victims wounded as Rhonda’s parents, Linda and Gerald Dorgan, and family friend Thomas Geruso.

All three remain in critical condition.