Footage aired by local media showed a gray-haired Mubarak walking with crutches into the courtroom accompanied by his two sons. 

Mubarak had initially refused to testify on grounds that his testimony “could harm national security”.

Regarding alleged border breaches that occurred shortly before Egypt’s popular uprising on Jan. 25, 2011, Mubarak said: “Omar Suleiman [then head of Egypt’s intelligence service] informed me of the breach, saying an 800-strong force had crossed the border.”

“They infiltrated the border from Gaza with the help of people in [Egypt’s] North Sinai province,” he added, claiming the latter had cooperated with Morsi’s Muslim Brotherhood “with the aim of sowing chaos in Egypt”.

The infiltrators, the former president alleged, “entered several prisons in the area, letting inmates affiliated with Hezbollah, Hamas and the Muslim Brotherhood go free”.

At one point, he added, “they climbed to the top of high buildings and began shooting”.

During his testimony, Mubarak pled ignorance in regards to a reported plan -- allegedly cooked up by the Brotherhood, Iran, Hamas, Hezbollah and the U.S. -- to drag Egypt into chaos.

He declined, however, to answer questions about government facilities that had been destroyed at the time and deaths that allegedly resulted in connection with these acts, according to an Anadolu Agency correspondent.

Morsi, for his part, appeared in a cage at the back of the courtroom, from which he appeared to be closely following Mubarak’s testimony.

It was the first time Mubarak and Morsi faced one another since the former stepped down in 2011 -- after three decades in power -- following 18 days of countrywide demonstrations. 

Morsi was elected president in 2012, one year after Mubarak stepped down. 

After a single year in power, however, he was himself ousted in a military coup and slapped with a host of criminal charges, which he and his supporters insist are politically motivated. 

Following Morsi’s ouster in mid-2013, the Egyptian authorities launched a relentless crackdown on political dissent, killing hundreds of Morsi’s supporters and throwing thousands behind bars for alleged “violence”.