The new Liberal senator Jim Molan has shared anti-Muslim videos on social media from Britain First, the far-right group that Donald Trump has been criticised for promoting.

Molan’s swearing-in on Monday was overshadowed by a report in Fairfax Media, confirmed by Guardian Australia, that he shared two racially inflammatory videos on his public Facebook page in 2017.

The first video, reposted by Molan on 12 March, depicts two incidents: one in which a young woman has her skirt pulled up and is slapped on the backside; another in which a young woman is punched and pushed to the ground by one youth and then kicked on the ground by another.

The video is tagged “Muslim thugs beat girl in Holland” by Britain First, although there is no evidence to suggest the violent incidents were motivated by religion and Dutch news sites have reported the latter altercation was actually about a scooter collision.

One commenter noted that the video was a fake, citing a fact check on the Snopes website, and asked for the video to be removed. But several others called for the people depicted in the video to be deported.

“Charming. And we’re meant to be tolerant, accepting and welcoming of this ‘breed’ in our country,” one commenter said, to which Molan replied “unbeleivable” (sic).

The second video, reposted by Molan on 27 March, depicts youths kicking, punching and throwing objects at police cars and is tagged “French police enter Muslim no go area” by Britain First.

The video contains no hint as to the cause of the altercation or verifiable source. Two cries of “Allahu Akbar” are audible in the 37-second long clip.

Molan told the ABC that the videos he reposted were not racist.

The Liberal senator Jim Molan after being sworn in at Parliament House. Photograph: Lukas Coch/AAP

“I’ve put my life on the line for Islamic countries ... for people to say this is racist I find deeply offensive,” he said.

A spokesman for Molan defended the posts by saying that he “often posts material in order to generate debate”, Fairfax reported.

“The sharing of any post does not indicate endorsement,” he reportedly said.

Molan, a retired general and one of the architects of the Coalition’s Operation Sovereign Borders policy, replaced the Nationals senator Fiona Nash, who was found ineligible by the high court due to her dual citizenship.

Before the revelations about the far-right videos, the former prime minister Tony Abbott praised Molan as a “wonderful man” and “great servant for our country in uniform and now out of uniform”.

“It’s wonderful that serendipity has got him into the Senate,” Abbott told 2GB Radio. “The [Liberal party] faction – the leftwing faction – did their damnedest to keep him out and, I guess, a happy side effect of the citizenship saga has been getting Jim Molan into the Senate.”

Last year Trump sparked global uproar when he shared three video tweets by Britain First’s deputy leader, Jayda Fransen. The British prime minister, Theresa May, said the president’s actions were “the wrong thing to do”.

“Britain First is a hateful organisation, it seeks to spread division and mistrust in our communities,” May said in Amman in December. “It stands in fundamental opposition to the values that we share as a nation – values of respect, tolerance and, dare I say it, common decency.”

In January, Trump offered to apologise for the tweets before a trip to the UK.