On Monday night Egyptian President Mohamed Morsi vowed to defend his presidency “with my life.”

Officials from his Muslim Brotherhood still making statements—many said they couldn’t speak—were likewise defiant in the face of a deadline imposed by Egypt’s top general that seems to spell Morsi’s ouster and possibly a crackdown on the powerful Islamist group. The deadline expires at 4 p.m. in Cairo, or 10 a.m. in New York. Mohamed Soudan, the foreign-relations chair of the brotherhood’s political party, warns of “endless violence and bloodshed” sparked by the group’s more extreme Islamist allies if the “coup” takes place. “It can be bloodshed. It can be civil war. And the Army knows that it can’t face that,” he says.

Mohamed Beltagy, a senior brotherhood official, said in a Web statement that Morsi’s supporters should prepare for “martyrdom.”

But Mohamed Habib, the former second in command of the brotherhood’s secretive ruling council, strikes a more somber tone. Morsi’s military-backed ouster was inevitable, he said in an interview Tuesday, and no threats of violence could prevent it. “They will do nothing,” he said of the brotherhood-allied extremist groups.

Many brotherhood leaders, Habib adds, would likely find themselves arrested or strong-armed into submission by police—in particular, midlevel officials who provide the link between the group’s leaders and lower ranks. Egypt’s Army chief, Gen. Abdel Fattah al-Sisi, Habib says, “will not do it unless he secures the land”—meaning that military action against Morsi would entail a crackdown on the brotherhood, too.

It’s hard to say what will become of the brotherhood once the clock expires on the 48-hour window al-Sisi gave Morsi to stem a crisis that has brought deadly clashes around the country and millions to the streets. But Habib, who left the group after 42 years in December 2009, says that the popularity that protected it through decades of repression had eroded drastically during Morsi’s year in office. “The Muslim Brotherhood was strong because it was popular among the people,” he says. “And in the last year it has lost its popularity.”

On Tuesday unconfirmed news reports suggested that some 50 members of the brotherhood and its Islamist allies had been barred from leaving the country, an ominous development for the group if true. Beyond the scope of the authorities, meanwhile, signs of popular anger against the brotherhood continued to mount. In addition to the millions who have taken to the streets against Morsi and the brotherhood, the group’s offices around the country have come under attack from angry mobs. On Tuesday a pro-Morsi rally at Cairo University was descended upon by anti-Morsi demonstrators, spiraling into deadly clashes.

Under Morsi’s predecessor, Hosni Mubarak, and the military-backed rulers before him, the brotherhood’s relationship with the Egyptian state vacillated between tolerance and brutal oppression. But the well-organized group emerged as Egypt’s most potent political force after Mubarak’s fall, dominating parliamentary elections and winning Morsi the presidency last June. But its support has waned consistently ever since, as Morsi and his allies seemed bent on consolidating power and critics charged that they were driving the country toward religious rule. Now many Egyptians who once supported Morsi and the brotherhood clearly have had enough.

Morsi’s televised remarks last night were his first since protests erupted Sunday. He offered little in the way of conciliation or concession, shouting angrily from the podium and hinting at the possibility of bloodshed. As he spoke, the crowd that had gathered to watch in one busy Cairo café alternately jeered and laughed in disbelief. “Fuck you!” some shouted at the TV screen, while others called him a “clown.” When Morsi promised that “tomorrow will be a better day,” one man replied, “Yes, because you will be in jail.”

Mohamed Ghonim, a prominent urologist and political activist who many in the opposition hope will play a role in a potential transitional government, said in an interview Tuesday night that any new leadership should pursue a policy of “reconciliation” toward the brotherhood. “The policy of Mandela should be adopted,” he says, “reconciliation with everybody except those people who are condemned—in a normal court—for criminal actions.”

He adds that the brotherhood should remain as a religious group, its inner workings and finances made transparent, while its political party should be allowed to press ahead. He said Morsi’s broken promises of an inclusive government and refusal to put forward concrete plans had doomed the brotherhood’s political project and eroded its public trust. “Everything which was declared and upon which the president was elected was false,” he says. “As you see now, Egypt has been divided and subdivided.”

But many brotherhood opponents have a more hostile outlook. “They have clashed with the society and with the future and with the state—the police, the Army, the judges,” says Abdullah Senawy, a journalist known to be sympathetic to the military. “So what's the scenario? Game over.”

With reporting by Maged Atef in Cairo.