The group, which includes a colonel and a lieutenant-colonel from the republican guard, are being prosecuted for "crimes against humanity by murder, malicious destruction and inciting soldiers to commit acts contrary to duty or discipline", according to a statement by the military court in Goma.
The charges were read out at the start of the trial on Tuesday, before it was suspended due to heavy rain. The soldiers were not yet asked to enter their plea.
The two officers, whose arrest was announced on Sunday, were in command of soldiers who opened fire on protesters, according to a source close to the presidency who asked not to be named.
Congo's government said 43 people were killed and 56 injured in the unrest in Goma last Wednesday. The U.N. human rights office said that the death toll could be higher.
The U.N. peacekeeping mission in eastern Congo, known as MONUSCO, has faced protests since last year spurred partly by complaints that it has failed to protect civilians against decades of militia violence.
An anti-MONUSCO protest in July 2022 resulted in more than 15 deaths, including three peacekeepers in Goma and the city of Butembo.
"The government's response is a step in the right direction, but a full and impartial investigation will have to look higher up the chain of command to ensure real justice," said Thomas Fessy, senior Congo researcher at Human Rights Watch.
He called on the government to investigate senior officials who may have been responsible for the operation, and to release civilians who were arbitrarily arrested.
(Additional reporting by Arlette Bashizi, Stanis Bujakera and Erikas Mwisi Kambale; Writing by Nellie Peyton; Editing by Hereward Holland, Alexandra Hudson)
By Ange Adihe Kasongo and Sonia Rolley
