The suspected shooter who opened fire at a Rhode Island high school hockey arena on Monday evening is a 56-year-old man who identified as transgender and made a number of alarming posts on social media prior to the shooting.

Team USA's men's hockey coach Mike Sullivan addressed the shooting at a Rhode Island high school hockey game, calling it a 'terrible tragedy.'

Rhode Island ice rink shooting suspect Robert Dorgan had a history of family conflicts over gender identity issues and a gender reassignment surgery, according to documents.

A shooting at a school hockey game in Pawtucket left multiple dead; teams from Blackstone Valley Schools were playing, and the suspect later died.