Russian authorities yesterday raised the official death toll to 143 in the terrorist attack on a Krasnogorsk concert venue, and Baza, a Telegram channel close to Russian law enforcement, reported that as many as 95 people are missing and not included on the lists of dead or wounded.

Russia media reports say the death toll from the March 22 Krasnogorsk concert hall attack rose to 143 and around 80 other people wounded in the siege by gunmen remain hospitalized.

This terrorist attack was the deadliest extremist attack in Russia in nearly two decades.  At least four gunmen toting automatic rifles shot at thousands of concertgoers and set the venue on fire.

The updated fatalities from Russia’s Emergencies Ministry didn't state the number of wounded, but Health Minister Mikhail Murashko reportedly said earlier Wednesday that 80 people were in hospitals and another 205 had sought medical treatment from the attack.

The report by Baza suggested that the final death toll could be substantially higher than 143.  Authorities have reportedly said some 360 people were wounded in the attack, with dozens still hospitalized.

The Washington Post reported on March 27 that the Islamic State (IS) terrorist group asserted responsibility for the attack, but senior Russian security officials, without citing evidence, have alleged that Ukraine, the United States and Britain had a role in organizing the strike.