Khamzat Chimaev kicked Sean Strickland – despite the presence of armed police on stage – as the pair faced off following an ugly news conference before UFC 328 on Saturday.

A bitter and personal exchange escalated even further when Chimaev, despite being held back by UFC security, beckoned Strickland towards him as the pair traded insults, before launching a kick at the American.

As the crowd roared, security and armed police escorted each fighter off stage in separate directions as they continued to hurl expletives at each other.

Tensions have threatened to boil over throughout fight week, with Russian-Emirati middleweight champion Chimaev set to defend his belt against American Strickland in Newark, New Jersey on Saturday.

It is not uncommon for UFC fighters to insult each other in the hope of building hype around a fight, but Strickland has been particularly volatile while addressing Chimaev – launching derogatory and racist comments which have attacked his religion and heritage.

Last week, Strickland threatened to shoot Chimaev if the 32-year-old and his team-mates confronted him in the build-up to the fight.

In response, the UFC has hired extra security to protect each fighter and reportedly kept the pair in separate hotels.

Chimaev has been calm and reserved during fight week, despite Strickland’s derogatory comments, but was animated during the news conference.

Before the pair had even taken their seats, security had to intervene and, as Strickland continued to goad Chimaev, he responded with ugly comments about childhood trauma which the American has spoken about in the past.

“You’re making fun of child abuse,” replied Strickland, who followed up with further expletives.

When asked if he enjoyed the bitter rivalry between Chimaev and Strickland, UFC president Dana White – who was stood between the pair – responded “it is what it is”.

He previously described it as a “top-three” heated rivalry of all time in the UFC.

Despite the offensive comments from Strickland and Chimaev, it is unlikely the UFC will take any disciplinary action with White a vocal supporter of free speech.

“I think probably the most important free speech to protect is hate speech,” White said last year.

“Because when a government or a certain person can come out and determine saying ‘this is hate speech’, it’s a very slippery slope and it’s dangerous, in my opinion.”

Strickland did not appear to be hurt by Chimaev’s kick and afterwards wrote “exactly what I expected a coward to do”, on social media.

It is unclear whether the New Jersey Athletic Control Board will punish Chimaev for the altercation.