Islamic State group (ISIS) has claimed credit for the brutal shooting spree in Vienna that killed four people and injured 14 others on Monday night. The group said it in a statement on its Telegram channels.

The statement which identified the gunman as "a soldier of the caliphate" was shot dead by police after a brief gunfight.

According to police officials, he was a 20-year old radicalized IS symphatizer named Kujtim Fejzulai, a dual citizen of Austria and North Macedonia. He was sentenced to 22 months in prison last year because he'd attempted to travel to Syria to join the so-called Islamic State. He was released seven months later due to laws applying to young adults.

Interior minister Karl Nehammer said police searched 18 properties as well as the suspect's apartment and detaining 14 people associated with the assailant who are being questioned.

Nehammer described Fejzulai as an "Islamist terrorist".

The shooting began at 8pm on Monday evening near Vienna's main synagogue, as many people were enjoying a last night of open restaurants and bars before a month-long coronavirus lockdown, which started at midnight.

The attacker had been armed with an automatic rifle, a hand gun and a machete, and had been wearing a fake suicide vest. He had posted a photograph of himself with the weapons on his Instagram account before the attack.