Cairo (CNN) -- A stern Egyptian court ruling tied to a soccer riot spurred clashes that left at least 30 people dead on Saturday, the latest round of violence in the unsettled North African nation.
In addition to those killed, more than 300 were wounded when people in the northeastern city of Port Said clashed with authorities outside a prison where their kin were being held, the head of Port Said hospitals told state-run Nile TV.
They were angry because 21 of their relatives had just been sentenced to death for their role in a February 1 riot in a Port Said stadium.
That 2012 incident -- during a game between Cairo's prestigious Al-Ahly football club and the host Al-Masry team -- ended with 73 dead.
Two months later, Egypt's general prosecutor charged 75 people with "premeditated murder and attempted murder," while three Al-Masry officials and nine police officers were charged with "assisting the murderers."
According to the prosecutor's office, those in the latter group knew about the assault ahead of time, didn't confiscate weapons in advance, didn't stop them and -- in the case of an electricity engineer who was charged -- turned off the lights directly over the bleachers where the Al-Ahly fans were sitting right after the visiting team wrapped up its 3-1 victory.
Fans from both sides bashed each other with rocks and chairs, yet prosecutors claimed the Port Said supporters were also armed with knives and other weapons.
Many died after falling from bleachers inside the stadium, while others suffocated.
It was unclear whether intense sports rivalries or political strife sparked the riot, though witnesses said tensions had grown throughout the game with Al-Masry fans throwing bottles and rocks at the opposing players.
That violence begat more on Saturday, after some of the defendants' relatives tried to storm the Port Said prison to free their loved ones being held inside, Interior Ministry spokesman Brig. Gen. Osama Ismail told Nile TV.
The reaction was far different in Cairo, where Saturday's verdict was issued due to security concerns.
One man cried for joy, feeling that "justice has been survived" following the death of his oldest son, the married father of two children.
"I finally felt that I am in a civilized country," added a woman in Cairo's capital. "My son (did) nothing wrong. But my son's legacy will live on, because of the true justice served here."
Egypt embroiled in deadly political unrest
Saturday's Port Said violence comes on the heels of other bloodshed around the nation, which was tied more explicitly to unrest about Egypt's current leadership but nonetheless symptomatic of instability and insecurity two years after longtime President Hosni Mubarak was ousted.
More recently, protesters have focused their anger at current President Mohamed Morsy.
The former Muslim Brotherhood leader, who became Egypt's first democratically elected leader last year, has come under fire by some who compared him to Mubarak and said he amassed power for himself and his Islamist allies. He has insisted his moves were necessary to move Egypt forward in the face of pressing issues and persistent obstacles.
On Friday -- the anniversary of what some call the January 25 Revolution -- six people were killed in Suez and one in Ismailia, amid clashes involving anti-government protesters and those supportive of Morsy, as well as police. Hundreds more were injured in the unrest nationwide.
Referring to this violence and what happened Saturday in Port Said, Information Minister Salah Abdul Maqsoud read a statement on state TV saying the government was considering implementing a state of emergency in some areas.
"The (National Defense Council) denounces the acts of violence and demands all national and political forces be committed to the peaceful ways to express their opinion," Maqsoud said after a meeting led by Morsy. "(The council) calls for wider national dialogue, led by (prominent) figures, to discuss the issues of political disagreement and reach national accordance."
On Saturday in Suez -- about 90 miles south of Port Said -- the government deployed troops and armored military vehicles in response to the previous day's clashes.
Brig. Gen. Adel Refat, the head of security in Suez, asked for the help after declaring the area "out of control," according to state news. Protesters accused Egyptian forces of opening fire during the demonstrations, a claim Refat strongly denied.
Meanwhile, in Cairo, clashes extended to areas around the Shura Council, the upper house of parliament. Protesters overnight waged a standoff outside the Nile TV offices, with some tossing Molotov cocktails and police responding with tear gas.
Journalist Ramy Francis and CNN's Reza Sayah reported from Cairo; CNN's Amir Ahmed reported Atlanta. CNN's Chelsea J. Carter, Greg Botelho, Yousuf Basil and Hamdi Alkhshali contributed to this report.