Police in Leipzig, Germany arrested six Antifa far-left extremists following a riot which led to thirteen officers being injured by leftist attacks.

The six suspects were soon released following their arrest, with a police spokeswoman saying that officers had no grounds to keep them in detention but an investigation into the four men and two women, aged between 18 and 39, would be launched, Bild reports.

The riot took place on Saturday evening following a demonstration by leftist extremists against the ban on the radical website Linksunten which was banned by the German government in 2017, following the massive Antifa violence at the Hamburg G20 that year that saw hundreds of police officers injured.

Aus dem Demonstrationszug heraus werden Böller und Pflastersteine auf Polizisten geworfen. +++ Hier geht's zum Demo-Ticker https://t.co/R0pAvB2IkP #le2501 pic.twitter.com/8ETlmPukv9 — LVZ (@LVZ) January 25, 2020

According to Bild the thirteen officers were attacked by Antifa extremists wearing hoodies and masks and armed with stones and fireworks and were treated for minor injuries.

Linksunten, the subject of the demonstration, was previously used by Antifa and other anarchist extremists to take credit for attacks along with post information such as the PRISMA booklet that instructed readers on how to build firebombs and sabotage infrastructure.

Indymedia, the platform which hosted Linksunte, remains online and many Antifa members continue to make posts claiming responsibility for attacks, including the brutal attack on populist Alternative for Germany (AfD) MP Frank Magnitz last year in Bremen.

Several journalists also reported being threatened by Antifa extremists during the demonstration.

Antifa has threatened journalists in the past, including mainstream journalists in Canada.

In 2017, the group, which U.S. President Donald Trump has considered labelling a terrorist organization, made threats to harm mainstream journalists in Quebec after previously attacking a camera crew of broadcaster Global News.

The riots are just the latest acts of violence from Antifa in Leipzig who have become increasingly active and increasingly violent in recent months, carrying out arson attacks on construction sites leading to millions of euros in damage and attacking an employee of a construction company in her own home.

Antifa Viciously Beat Female Real Estate Employee in Her Home https://t.co/Oba3qwEvmc — Breitbart London (@BreitbartLondon) November 6, 2019