A 45-year-old man and a 40-year-old woman have been taken to the hospital with gunshot wounds from Moscow Regional Court, said Moscow Region's Health Ministry, as quoted by Russian Federation news agencies. As a result, three suspects were killed on the scene, two more were wounded, while one of the National Guards' officers sustained a gun wound in a shoulder.
In the carnage that followed three of the defendants tried to escape but were shot dead by security officers.
Russia's Investigative Committee said the incident happened when five handcuffed defendants were escorted by two guards in a lift.
Speaking from Moscow, Al Jazeera's Rory Challands said that the three defendants were members of a gang that were involved in "one of the more lurid episodes of Moscow's recent past".
They were on trial for being part of a "Grand Theft Auto" gang where motorists where forced out of their cars and killed.
The gang supposedly gained its name as the members attacked vehicle owners on highways copying the popular Grand Theft Auto game franchise.
Five men were standing trial at a Moscow courthouse where a shooting occurred in the building. They are charged with 17 murders, two attempted murders, banditry, plunder, illegal production and possession of weapons as well as with stealing documents.
The standoff ensued after some of the suspected gang members attacked the two officers accompanying them in an elevator in an attempt to escape.
Some people were injured in a shootout in the Moscow Regional Court, lawyer Sofya Rubasskaya told Sputnik on Tuesday. "Then we heard shots - approximately 25 shots were fired".
The two wounded defendants were disarmed and detained.