CAIRO - Egypt’s armed forces warned on Monday that it will intervene if the people’s demands are not met within 48 hours, after millions took to the streets to demand the resignation of President Mohamed Morsi.

In a statement read out on state television, the armed forces reiterated its “call that the demands of the people be met and gives (all parties) 48 hours, as a last chance, to take responsibility for the historic circumstances the country is going through.”

“If the demands of the people are not met in this period... (the armed forces) will announce a future roadmap and measures to oversee its implementation,” the statement said.

Earlier, Egypt’s opposition gave Morsi a day to quit or face civil disobedience after deadly protests demanded the country’s first democratically elected president step down after just a year in office.

“We give Mohamed Morsi until 5:00 pm (1500 GMT) on Tuesday July 2 to leave power, allowing state institutions to prepare for early presidential elections,” the Tamarod movement said in a statement on its website.

Otherwise, “Tuesday, 5:00 pm will be the beginning of a complete civil disobedience campaign.”

The health ministry said 16 people died in nationwide protests, including eight in clashes between supporters and opponents of Morsi outside the Cairo headquarters of the Muslim Brotherhood movement from which he hails.

Another three people died in the central province of Assiut and one each in Fayoum, Beni Sueif and Kafr el-Sheikh provinces.

One protester suffocated to death at a rally outside the presidential palace in Cairo and another died of wounds in the coastal city of Alexandria, the ministry said.

Early on Monday, protesters set the Brotherhood’s headquarters ablaze before storming it and ransacking it, an AFP correspondent reported. Looters left with petrol bombs, helmets, flak jackets, furniture, televisions and documents.

“This is a historic moment. The Brotherhood ruined the country, so stealing from them is justified,” one told AFP.

A senior government official told AFP that four ministers - tourism, environment, communication and legal affairs - had tendered their resignations to Prime Minister Hisham Qandil.

Tourism minister Hisham Zazou had already tried to resign last month after Morsi appointed Adel al-Khayat, a member of an Islamist party linked to a massacre of tourists in Luxor, as governor of the temple city.

Monday’s resignations were a further blow to Morsi, who since coming to power has battled with the judiciary, the media and the police.

Tamarod - Arabic for rebellion - is a grassroots campaign which says it collected more than 22 million signatures to a petition declaring a lack of confidence in Morsi.

It was behind Sunday’s protests that saw millions of people demand his departure on the first anniversary of his inauguration.

As Morsi stood firm and insisted the only way forward was dialogue, calls for army intervention increased.

Tamarod urged state institutions to support the protesters, calling on “the army, the police and the judiciary to clearly side with the popular will as represented by the crowds”.

Opposition leader Hamdeen Sabbahi urged military intervention if Morsi refused to quit.

The army, which led a tumultuous transition after Mubarak’s ouster, had already warned it would intervene if there was major unrest.