Giza, Egypt (CNN) -- Egypt declared a state of alert as the country's Cabinet prepared to meet in emergency session Saturday to discuss an attack on the Israeli Embassy, a government spokesman said.
Mohamed Hegazy, the spokesman for the prime minister, announced the alert and the canceling of police holidays after Egyptian protesters tore down a wall surrounding the building that houses the Israeli Embassy and entered its offices.
Once inside, the protesters threw papers bearing Hebrew from the windows and into the streets. The offices were empty because Friday is a weekend day in Egypt.
Police fired tear gas into the crowd and gunshots into the air outside the building, which is across the Nile River from Cairo. A police car in front of a nearby police headquarters was set afire.
Earlier, as demonstrators destroyed the wall that had protected the high-rise building, police and military forces took no action.
But 450 people were injured in clashes as protesters hurled bottles at police in back streets, the minister of health told MENA, Egypt's official news agency.
One man died of a heart attack after the protests, said Army Lieutenant Colonel Amr Imam.
Protesters cheered the demolition and chanted for the ouster of Israel's ambassador. The demonstrators were among thousands of Egyptians who took to the streets Friday.
Many protesters converged on Cairo's Tahrir Square to demand reforms in a turnout they had dubbed "correcting the path of the revolution." Egyptian state TV reported that hundreds of people attempted to raid the Interior Ministry and crowds of demonstrators gathered in front of the state TV building.
Israeli Foreign Ministry spokesman Yigal Palmor said about 3,000 protesters had torn apart the wall circling the embassy building.
An Egyptian commander at the embassy told CNN that security personnel had been ordered to avoid confrontations with protesters.
Police had been guarding the entrance to the building, which houses the embassy on the 12th floor and private dwellings on other floors.
The commander said the wall had been erected recently to protect the residents, not the Israeli Embassy.
Since the ouster in February of President Hosni Mubarak, many Egyptians have called for the end of diplomatic relations with the Jewish state. The two nations signed a peace treaty in 1979.
Egyptians have been angry about the killing of five Egyptian police officers by Israeli soldiers last month when Israel went after militants who had attacked civilians near the Israeli-Egyptian border.
Meanwhile, protesters at Tahrir Square criticized the performance of the Supreme Council of the Armed Forces and the government in the wake of Mubarak's ouster.
The Interior Ministry had announced Thursday the square would be cleared of police and soldiers for 24 hours to allow for a smooth protest. It said its forces would intervene if government or public property were destroyed.
"We cleared the square to avoid any confrontations, but we expect violence within the groups and hope thugs don't take advantage of the situation," said Lt. Col. Amr Imam, Armed Forces spokesman.
Protesters want the abolishment of military tribunals, the establishment of minimum and maximum wages, permission for Egyptians abroad to vote in the coming elections and the announcement of dates for those elections.
They are also calling for the removal of former ruling party members from banks, schools, universities and government institutions.
Mubarak is charged with ordering the killing of protesters to quash the uprising that ultimately ended his 30-year rule. In addition, he faces corruption charges. He has pleaded not guilty to the charges.