A member of the prestigious Cambridge University Conservative Association has been expelled from the organisation after he was filmed burning a £20 note in front of a homeless person.

The footage, shared on Snapchat, showed the Pembroke College student, dressed smartly in bowtie and tails, using a cigarette lighter to burn the money, the student website the Tab reported.

The person recording the video then captured a homeless man in the shot, who was standing outside a clothing shop in Cambridge city centre. After burning the money, the student says “some homeless shelter” before the video ends.

The Cambridge University Conservative Association (CUCA) said the student had been expelled. Its chairman, Joe Mathieson, told the Tab: “We were informed by people who had seen the video on Snapchat that he had behaved like this, and took immediate action to remove him.

“His membership was revoked immediately after the news came to the committee’s attention. This was on the basis that there is absolutely no place for people who behave like this in our association. That said, he was not acting in the capacity of a CUCA member, nor was he attending, or had attended, a CUCA event.

“For the record, CUCA has no initiations, does not condone behaviour of this kind in the slightest, and this was entirely independent of CUCA. We are as appalled as every other right-thinking member of the university.”

CUCA’s alumni includes the former cabinet minister Ken Clarke, who is a former chairman, and the former chief whip Andrew Mitchell and Lords Speaker Norman Fowler are both still honorary vice-presidents. The association’s honorary president is the historian Andrew Roberts, author of Napoleon the Great.

The mother of the student in the video told the Mail she did not recognise her son’s behaviour. She said he had spoken to the family after the incident and said he had done “something very stupid” and “felt really bad about it”.

“It’s completely out of character,” she said. “He did two years of volunteering at Stockbridge homeless shop in Edinburgh when he was still at school. It’s very surprising. We’re just a normal family. We’re not toffs, he’s not a toff. He’s been a hard-working student who is very, very lucky and aware of the privilege he has to study at Cambridge.”

A Cambridge University spokesperson said: “The university is committed to respecting the rights and dignity of all members of our community. We expect our students to treat others with respect, courtesy and consideration at all times, and the university takes allegations of unacceptable behaviour very seriously. We do not comment on individual cases.”