Portland, which has become the base of operations for the alt-left Antifa movement, was once again rocked by violence as pro-Trump and anti-Trump demonstrators squared off against each other on Sunday.

Fourteen arrests have been made thus far, and city police have seized numerous weapons from Antifa members, including dynamite, brass knuckles, wooden bats, and knives.

Antifa members assault law enforcement with feces and used tampons

According to Fox News, the anti-Trump protesters hurled bricks and glass bottles at police officers in Chapman Square, while eyewitnesses claim that other Antifa members hurled bloody tampons and rubber balloons filled with feces at Trump supporters and police officers alike.

A few blocks north of the Chapman Square pro-Trump rally, police held back a large crowd of protesters and journalists, threatening them with charges of disorderly conduct. One reporter for the Portland Tribune was also arrested but later released.

Portland mayor's assault on free speech.

Sunday's violence comes in the wake of a deadly stabbing in Portland that claimed the lives of two men who attempted to confront the attacker after he began shouting anti-Muslim slurs at two females.

While several media outlets were quick to blame Donald Trump for inspiring the incident, social media posts revealed that the 35-year-old attacker, Jeremy Joseph Christian, was an ardent Bernie Sanders and Jill Stein supporter.

As a result of the knife attack, Mayor Ted Wheeler attempted to revoke the permit of the the pro-Trump demonstrators, claiming that their presence might incite violence.

Federal officials stepped in and said that such an action would be a violation of the First Amendment rights of Trump supporters, adding that there was "no basis" for revoking the permit.

The traditionally left-leaning Oregon ACLU also defended the right of Trump supporters to rally, calling Mayor Wheeler's actions "wrong" and "unconstitutional."

Patriot Prayer, the conservative group behind the Portland pro-Trump rally, denied having any connection with Jeremy Joseph Christian and disavowed the killer's actions.

In spite of the evidence that Christian's actions were not motivated by Trump, counter-protesters who clashed with Trump supporters held up signs reading "Our city is greater than hate" and chanted "love, not hate" and "Go home, fascists."