The judge in the appeal trial of Egyptian activist Alaa Abdel-Fattah and 24 others ordered on Monday for mobile service providers to reveal the location of Abdel-Fattah's whereabouts on 26 November last year.
Abdel-Fattah and the 24 other defendants were arrested on that day on charges of illegal protesting, rioting, destruction of public property and using violence against security forces.
They are appealing 15-year prison sentences and fines LE100,000 (about $14,200) each.
Before adjourning the trial to 23 November, the judge ordered the country's three mobile service providers to reveal Abdel-Fattah's whereabouts from 4 to 7 pm on the day of his arrest as well as the whereabouts of police officer Emad Tahoun, whom Abdel-Fattah is accused of attacking during this time period.
Abdel-Fattah has denied the accusations.
One of the defence lawyers, Taher Aboul-Nasr, told Ahram Online that Abdel-Fattah left the protest at 4:30 pm, and thus the defence team asked the court to locate Abdel-Fattah and Tahoun's positions through their incoming and outgoing calls to prove that their defendant didn't attack the officer.
The defendants are to remain in jail pending the ongoing trial, despite lawyers requesting their release.
Rights activists have criticised the continued renewal of preventative detention for defendants in various cases, as trials drag on in courts.
Abdel-Fattah is currently on hunger strike to protest his arrest after a brief release from 15 September to 27 October.
He is also appealing a one-month prison sentence for insulting the "interior ministry," after a dispute with an officer while he was detained for the illegal protesting case.