A court in Cairo has convicted 26 men of plotting attacks in Egypt and of having ties with the Lebanon-based group Hezbollah.
The emergency state security court on Thursday also sentenced the suspects - of Palestinian, Lebanese, Egyptian and Sudanese origin - to prison terms ranging from six months to life terms.
The defendants were charged with spying on ships in the Suez Canal, planning attacks on holiday resorts popular with Israelis in Sinai, and smuggling weapons into the Gaza Strip.
"Hezbollah has been very quite and it seems like they don't want to exacerbate things," Al Jazeera's Jacky Rowland, reporting from Beirut, said.
"In the past, Hezbollah's leader, Hasan Nasrallah, didn't deny that there had been a cell operating in Egypt but did say that this was not planning any attacks to targets in Egypt but were there to help the Palestinian resistance in Gaza."
Of those convicted and sentenced on Wednesday, two were Lebanese, five Palestinians and 19 Egyptians.
Judge Adel Abdel Salam Gomaa said investigations proved the group intended "to strike Egypt's economy, destroy the bonds between its people and create chaos and instability throughout the country".
Three defendants who were on the run and tried in absentia, including Mohammed Qublan, the suspected Lebanese leader of the group, were given life sentences.
Sami Shehab, the second defendant, and Mahmoud Nimr, a Palestinian, got 15-year prison sentences.
Another 10 were given 10 years in jail, with the rest of those present receiving between three and seven years, and one defendant getting six months.
No higher appeal
No higher appeal is possible for the case, with the only possibility or recourse being a presidential pardon.
Al Jazeera's Amr El-Kahky, reporting from outside the courthouse, said the verdicts were tougher than expected, although there were no death sentences handed down.
"The defendents were not happy with these verdicts, of course. And they described the court as the state security court of Israel, not of Egypt," he said.
Family members had gathered outside the court before the announcement of the trial's verdict, shouting "God save you" to the defendants.
The courthouse itself was surrounded by hundreds of Egyptian soldiers and police.
Hassan Nasrallah, leader of Hezbollah, had admitted earlier that one of the men was an agent for the movement but denied any plan to harm Egypt.
He said that the Hezbollah member had been assigned to smuggling weapons to Palestinian fighters in Gaza.
In addition to weapons smuggling and planning attacks, they were also charged with sending operatives into the occupied Gaza Strip to help Palestinian fighters there.