A human rights group suspects the Egyptian military of covering up its role in the deaths of the country's Coptic Christians.
The Human Rights Watch has called for an independent investigation into the deaths of 27 people killed during violent clashes with Egyptian security forces on Oct. 9.
"The military cannot investigate itself with any credibility," Joe Stork, deputy Middle East director at Human Rights Watch wrote on the HRW website.
Video footage shows military vehicles plowing through the demonstrators in Cairo, killing and injuring protesters.
"This had been an essentially peaceful protest until the military used excessive force and military vehicles ran over protesters," Stork said.
"The only hope for justice for the victims is an independent, civilian-led investigation that the army fully cooperates with and cannot control and that leads to the prosecution of those responsible," he said.
Of the 28 people arrested so far, none are soldiers.
At a press conference on Oct. 12, Gen. Adel Emara told reporters soldiers neither opened fire nor intentionally ran over any of the demonstrators.
"The soldiers driving armored vehicles were trying to avoid protesters, who were throwing stones and Molotov cocktail bombs at them," Emara told the press.
Egyptian state media reports that the interim military government is working to resolve the issues Christians have with the government.