Egypt Brotherhood chief, deputy get life for 'spying'
They included the Brotherhood's supreme guide Mohamed Badie and his deputy Khairat al-Shater who were both handed life sentences - 25 years in Egypt.
This is the latest of several sentences against Badie, who received a life sentence last week on charges related to mass prison breaks during the 2011 uprising.
Five other Brotherhood members were sentenced to jail terms ranging from seven to 10 years while six were acquitted, the source said.
The defendants were accused of "committing crimes in collaboration with foreign organisations" namely Hamas and the Lebanese Shiite militant group Hezbollah, the source said.
They were also accused of "financing terrorism" and committing acts undermining the country's stability and security.
Mohamed Fahmy, the judge presiding over the case, said before the verdict was announced: "The crimes the defendants committed harmed the independence and security of the country."
"They betrayed their nation and there is no excuse for them," he added.
The verdict can still be appealed, the source added.
Charges were also dropped Wednesday against the late former president, Mohammed Morsi, who collapsed and died in June during a court session on the case.
Morsi, 67, was elected president in 2012 in the country's first free elections following the ouster of longtime autocrat Hosni Mubarak in 2011.
A military coup toppled Morsi in 2013 after massive protests. The military, led by then-defence minister Abdel Fattah al-Sisi, crushed the Brotherhood in a major crackdown and arrested Morsi and many of the group's leaders.
Comment: When Morsi was ousted, so was Egypt's democracy
Authorities have since branded the Muslim Brotherhood a terrorist organization and arrested thousands of its members.
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