Several contestants have walked out of a Miss Universe event after an official from host nation Thailand publicly berated Miss Mexico in a tense confrontation.

At a pre-pageant ceremony, Miss Universe Thailand director Nawat Itsaragrisil told off Fatima Bosch in front of dozens of contestants for failing to post promotional content.

When she objected, Mr Nawat called security and threatened to disqualify those supporting her. Ms Bosch then left the room and others joined her in solidarity.

Video of the incident, which was live streamed, has been shared online. The Miss Universe Organisation (MUO) has condemned Mr Nawat's "malicious" behaviour, for which he has since apologised.

The Miss Universe contestants, who are the winners of national pageants in their home countries, attended Tuesday's event in their sashes and gowns.

Some can be heard shouting back at Mr Nawat in the video, after he raises his voice to reprimand Ms Bosch and repeatedly tells her to stop talking.

As many of them stand to show support, Mr Nawat says: "If anyone wants to continue the contest, sit down. If you step out, the rest of the girls continue."

Despite this, the majority of the women in the video appear standing, with several heading towards the door.

After leaving the event on Tuesday, Ms Bosch told the press the 60-year-old executive was "not respectful" and said he had called her "dumb".

Mr Nawat has disputed this, claiming his words had been misunderstood.

He is widely reported to have called the 25-year-old a "dumbhead". But at a press conference he later claimed he was saying she had caused "damage".

His conduct prompted a stern rebuke from the MUO, which has sent a delegation of international executives to take over running the competition.

In a video statement, MUO President Raul Rocha said Mr Nawat had "forgotten the true meaning of what it means to be a genuine host".

He said the Thai official had "humiliated, insulted and showed a lack of respect" to Ms Bosch, and committed the "serious abuse of having called security to intimidate a defenceless woman".

Mr Nawat's participation in the pageant would be limited "as much as possible" or eliminated entirely, he said, adding the MUO would be taking "legal actions" against him.

"I wish to reiterate that Miss Universe is an empowerment platform for women so that their voices can be heard in the world," Mr Rocha said.

Among those to walk out on Tuesday was reigning Miss Universe Victoria Kjaer Theilvig of Denmark.

"This is about women's rights," she said as she left the event. "This is not how things should be handled. To trash another girl is beyond disrespectful... That's why I'm taking my coat and I'm walking out."

Ms Bosch later said in an interview: "I just want to let my country know, I'm not afraid to make my voice heard. It's here stronger than ever. I have a purpose. I have things to say.

"We're in the 21st century. I'm not a doll to be made up, styled and have my clothes changed," she added.

"I came here to be a voice for all the women and all the girls who fight for causes and to tell my country that I'm completely committed to that."

Video of Mr Nawat has outraged fans of the pageant, with many heavily criticising his actions and praising Ms Bosch's response.

In a social media video statement, Mr Nawat said: "If anyone feels bad, uncomfortable, or affected, I apologise to everyone. I especially apologised to the girls who were present, around 75 of them."

The Miss Universe competition has pressed on despite this controversy, with contestants taking part in a welcome event in Bangkok on Wednesday.

The winner will be crowned the new Miss Universe on 21 November. (BBC)