Nineteen people have been jailed over an attack at a concert hall near Moscow that killed 149 people and left more than 500 injured, the deadliest mass shooting in Russia in two decades.

A Russian military court handed life sentences to four gunmen and 11 accomplices. Four other defendants were given between 19 and 22 years, state media reported.

Gunmen opened fire at Crocus City Concert Hall on the outskirts of Russia’s capital on 22 March 2024 and set fire to the venue.

An Islamic State affiliate group claimed responsibility for the attack and posted video evidence. Moscow has repeatedly alleged Ukrainian involvement, which Kyiv has strenuously denied.

The attackers then set fires which engulfed the venue and caused the roof to collapse. Many of the victims died from bullet wounds and some from smoke inhalation.

The four men convicted of carrying out the shooting are all citizens of Tajikistan, according to Russia’s state news agency Tass.

It is not clear how the defendants pleaded or whether they will appeal.

The trial has been conducted behind closed doors and there are likely to have been confessions made under duress.

IS-K, the group which claimed responsibility for the shooting, is an ISIS offshoot which seeks to establish a Muslim caliphate across Afghanistan, Pakistan, Turkmenistan, Tajikistan, Uzbekistan and Iran.

Graphic video released by ISIS, showing attackers firing on the crowd inside the concert hall, was verified as genuine by the BBC.

Russian officials have continued to claim that Ukraine was linked to the attack – the neighbour Russia has been at war with since it launched a full-scale invasion in 2022. No evidence has been provided for the claims.

Ukrainian officials fiercely deny any connection.

President Volodymyr Zelensky previously said it was “absolutely predictable” that Russian President Vladimir Putin would blame it on Ukraine.