Named by police as Chris Harper-Mercer, the shooter was shot dead by officers after the incident at Umpqua Community College in Oregon.

Pictures uploaded in 2014, showing support for the IRA, were posted to his MySpace account, along with captions saying “looking cool defending their country” and “have faith and keep fighting”.

A video was also posted, showing IRA members wielding weapons and wearing balaclavas.

^{Pro-IRA images on Chris Harper-Mercer’s MySpace profile.}

It appears Harper-Mercer also showed admiration for Vester Lee Flanagan, the disgruntled former journalist who shot dead two previous colleagues during a live news broadcast in Virginia in August.

“His face splashed across every screen, his name across the lips of every person on the planet, all in the course of one day.

“Seems the more people you kill, the more you’re in the limelight.

“People like him have nothing left to live for, and the only thing left to do is lash out at a society that has abandoned them.”

He continued: “He posted the footage on Facebook and Twitter as well tweeting while he was running from the cops because he wanted the world to see his actions, much like many others post menial and trivial details of their life online and expect us to see it.

“Only his was at least a bit more interesting.”

“I have noticed that so many people like him are all alone and unknown, yet when they spill a little blood, the whole world knows who they are.”

On an online dating profile, Harper-Mercer described himself as “shy at first, but warm up quickly, better in small groups”.

His username on the dating site Spiritual Passions was ironcross45 – a reference to the German military symbol reintroduced by the Nazis.

The 26-year-old is thought to have originally been from the UK.

His stepsister, Carmen Nesnick, was quoted by CBS Los Angeles as saying: “I’m actually still shaking and my mom is in there crying. I don’t know what to do.”

She said Harper-Mercer had moved to the US as a young boy and described him as “caring and supportive”.

She also claimed he was not a religious or anti-religious person, adding: “All he ever did was put everybody before himself. He wanted everyone to be happy. No matter if he was sad or mad, he would always try to cheer up everybody.”

Harper-Mercer’s father said he was “shocked” after a “devastating day”.

It is understood the shooter demanded to know his victims’ religious beliefs before opening fire but a motive has not yet been confirmed by police.

Several people remain in hospital after what was the 45th school shooting in the US this year.

^{A candlelight vigil was held in the Oregon town of Roseburg on Thursday night. ©Getty}

Earlier deputy First Minister Martin McGuinness expressed his condolences to the families of the victims of the massacre.

He said his thoughts and prayers are with the families involved.

“I was shocked and saddened to hear that so many young people have been shot dead in a deranged attack, in what should have been a place of safety and learning,” he said.

“I extend my condolences to all the families of the victims at this awful time of grief and mourning and wish those injured a full and speedy recovery.”

Local authorities have said they are investigating the incident.

Original story UTV News