John Greyson, a Toronto filmmaker, and Tarek Loubani, a physician from London, Ontario, have been jailed in Cairo since Aug. 16, the Toronto Star reported Tuesday.
The men face more than a dozen charges, with the most serious being murder, "intention to kill," aiding and abetting murder and "using explosives against the Asbakiya police station."
Formal charges have not yet been filed against them, but an Egyptian court has extended their detention another 45 days to allow the Egyptian attorney general to continue his investigation.
The men have denied all charges. Their lawyers say they should be released because there in no credible evidence against them.
Greyson and Loubani have said they arrived in Egypt intending to go to Gaza, where Loubani planned a medical teaching mission and Greyson was to film him.
When the outbreak of violence prevented them from crossing into Gaza, the men said they ventured to Ramses Square, where members of the Muslim Brotherhood were protesting the ouster of President Mohamed Morsi. Loubani cared for wounded protesters while Greyson filmed the scene.