Mass protests and strikes involving tens of thousands of workers and youth brought the Suez Canal city of Port Said—one of the major industrial cities in Egypt and home to the second busiest port in the Arab World—to a halt on Monday.

Protesters blocked the entrances to the city, while canal workers at the Port Said arsenal, run by the Suez Canal Authority, closed the gates to the shipyard. Nearly 40,000 workers at 29 factories in the industrial free zone went on strike, and schools and government offices were closed.

From early in the morning workers and youth marched through the city demanding the ouster of US-backed President Mohamed Mursi and his Muslim Brotherhood-led government. They chanted “Leave, Mursi, leave!” and “As long as Egyptian blood is cheap, down with any president!” At 7 AM protesters convened outside the provincial government headquarters, barring entrance to the building.

During the day demonstrations intensified, with protesters blocking railways while other sections of workers and youth went on strike or joined the protests. These included students, teachers, and employees of the provincial government, the courts, the telephone company, the natural gas utility, the customs office and other institutions.

The New York Times reported nervously that “the protests marked the closest that the chaos in Egypt over the last two years has come to threatening the operations of the Suez Canal, an artery of shipping critical to both international commerce and the battered Egyptian economy.”

Army reinforcements were called in to protect the operations of the port and the Suez Canal and secure vital government buildings. The military also moved into the industrial zones to guard the factories. Mahmoud Qandil, a protester and accountant, told Daily News Egypt that “one of the factory owners fired shots into the air to disperse protesters, who responded by pelting the factory with rocks, causing minor damage.”

The military was not able to control or stop the protests. Qandil said that, “the military ruler in Port Said, Major General Adel El-Ghadban, tried to negotiate with workers to end the disobedience, but they refused.” Instead, workers called for the downfall of El-Ghadban.

The mass strikes and protests exploded after thousands marched on Sunday demanding the dismissal of Interior Minister Mohamed Ibrahim as well as justice for the martyrs of the revolution and the immediate lifting of a night-time curfew in the city.

President Mursi last month deployed the army and ordered a 30-day state of emergency in the three Canal cities—Port Said, Suez and Ismailiya—in an effort to curb renewed protests that have swept Egypt since January 25, the second anniversary of the outbreak of the Egyptian revolution that toppled long-time dictator Hosni Mubarak in February 2011.

In Port Said, protests assumed an insurrectionary character on January 26 when a court sentenced 21 fans of Port Said’s Al-Masry Football Club to death for their alleged involvement a deadly football riot a year ago. At least 40 protesters have been killed and 250 wounded since the January 26 events.

Over the weekend, strikes and protests erupted in other major cities across the country. In the capital, Cairo, hundreds of doctors demonstrated Sunday outside the Egyptian Ministry of Health to demand higher salaries and better working conditions.

In the coastal city of Alexandria, Central Security Forces on Sunday broke up a sit-in strike by 450 workers at the Portland Cement Company, freeing managers who had been detained by the workers. In the course of the crackdown, 100 workers were arrested and dozens injured by police dogs.

In the Nile Delta city of Mahalla, a center of the textile industry with a long history of militant struggles, protests took place against Mursi and the Muslim Brotherhood. Protesters and security forces clashed Sunday night, with demonstrators attacking the local police station with rocks.

Two days before, a protester was killed during a demonstration demanding justice for Mohamed El-Gendy, an activist who was tortured to death by police two weeks ago.

Underlying the intensification of the class struggle are the growing social divisions in Egyptian society. Two years after the initial mass struggles, the social and economic conditions of broad layers of workers and youth have worsened. Like his predecessor Mubarak, Mursi is seeking to drive working class living standards, already at the poverty level, even lower.

A recent study by the Egyptian Centre for Economic and Social Rights (ECESR) reported a sharp rise in strikes and protests in 2012, particularly since Mursi and the Muslim Brotherhood came to power. According to the study, 3,817 protests and strikes were staged in the past year, with 2,700 of those taking place under Mursi.

The increasingly dominant role played by the working class indicates the beginning of a new stage of the Egyptian revolution, now entering its third year. The latest strikes and protests have erupted outside the control of and in direct conflict with all factions of the bourgeois elite, which are closing ranks in the face of a developing social revolution from below.

On Saturday, Mohamed ElBaradei, the leader of the oppositional National Salvation Front (NSF), received Saad El-Katatni, head of the Freedom and Justice Party (FJP), the political arm of the ruling Muslim Brotherhood, for a private meeting at his home. Before the meeting, ElBaradei stressed the need for “real national cooperation” with the Islamists to secure a $4.8 billion loan from the International Monetary Fund. The secular bourgeois leader called for “political stability and a return of security.”

At the same time, the Egyptian ruling class is responding to the mounting threat from below by turning to ever more violent forms of repression. The ECESR study notes that these include “dismissals, suspensions, transfers outside or inside headquarters, detentions, beatings and lynchings, pay cuts, administrative investigations or general prosecutions, threats and terror, assaults by thugs at the incitement of business owners, and the threatened or actual closure of companies.”

On Saturday, in the southern governorate of Beni Suef, police beat to death a man named Hossam Abo El-Regal, whom they accused of shooting a police officer. According to Ahram Online, they brought El-Regal to the funeral of the police officer, “tied him down on a mini-truck, and beat him to death.”

The murder took place “in the presence of senior security and political officials in Beni Suef who were leading the procession, including General Ahmed Shaarawi, the governorate’s security director, and Maher Beybers, Beni Suef’s governor.”