An Arabic-speaking knifeman who killed one person and seriously injured another was taken down by members of the public, including a martial arts practitioner, who beat him unconscious in Rotterdam, the Netherlands.

Police say it’s too early to say what the motive for a stabbing attack in Rotterdam, the Netherlands’ second city on Wednesday night that saw a 32-year-old resident of the city killed, and another hospitalised with serious injuries, reports de Volkskrant. The suspect, a 22-year-old associated with the historic Dutch city of Amersfoort was beaten unconscious during the attack and is now under arrest and receiving treatment in hospital.

Witnesses say the knifeman shouted “Allahu akhbar” as he struck, the now well-known saying that has become so associated with terrorist attacks in Europe, and Geert Wilders, the Dutch anti-mass-migration politician who is now the power behind the country’s governing coalition reflected the emergence again of the phrase underlined “the Islamisation of the Netherlands”.

Dutch newspaper De Telegraaf states the attack started around 2000 local time in a parking garage under the approach to Rotterdam’s landmark Erasmus bridge (pictured, above), where a knifeman stabbed the individual who was evacuated to hospital alive, but with unspecified serious injuries. From the garage, the attacker when stabbed a man who was rollerskating on the Willemsplein, a popular public square by the bridge.

Members of the public rushed to try and revive the 32-year-old male roller-skater, but he died from his injuries. A personal trainer who witnessed the attack told the paper: “I looked up and saw a light-skinned man, in a dark jacket with a hood, stabbing him. He must have stabbed him at least twenty times”.

The knifeman then attempted to storm a waterfront restaurant but was chased off by diners who fought him with chairs and tables from the establishment. He then tried to gain access to a nearby museum, but had been chased by the chair-wielding diners and was subdued. The personal trainer, who had joined the fight by this time and was using some of his exercise equipment as a weapon against the knifeman, continued in his statement: “I gave him a few taps. I did Krav Maga, the Israeli martial art, on him.

“He was shouting and swearing in Arabic. I didn’t do it alone, but with the people from [the museum] who threw chairs and tables at him. He was unconscious”.

Police say they are aware of witness accounts saying the attacker shouted “Allahu akhbar” during the assault but say they won’t be calling a motive yet. They said in a statement: “We will include that in the investigation, but it is too early to label it at this time”.

The suspect, who is alleged to have carried two “large knives” into Rotterdam before launching an attack, is in police custody.