Egyptian security forces on Wednesday pulled the plug on a Muslim Brotherhood television station after the army announced the overthrow of Mohamed Morsi, an aide to the Islamist president told Agence France Presse.

The source added that workers with Al-Jazeera's Egypt affiliate, Al-Jazeera Mubashir, were also arrested after the channel aired a defiant speech by Morsi.

Egypt's new caretaker president Adly Mansour had been head of the Supreme Constitutional Court for just two days when the army named him leader of the Arab world's most populous state.

He takes the helm of a nation riven by deep divisions over the army's ouster of its first freely elected president Mohamed Morsi following days of deadly clashes between his Islamist supporters and their increasingly numerous opponents.

Following are key developments in Egypt since millions took to the streets Sunday to demand the resignation of Islamist President Mohamed Morsi, leading to his ouster by the army on Wednesday.

- Sunday, June 30:

Army chief Abdel Fattah al-Sisi laid out the details on Wednesday of a roadmap for Egypt after the ouster of president Mohamed Morsi which names the head of the Supreme Constitutional Court the country's caretaker leader.

Sisi, the defense minister in Morsi's government, also announced a freezing of the Islamist-drafted constitution and early presidential elections.

Mohamed Morsi, who was ousted by the army on Wednesday after a week of bloodshed and massive protests, insisted he remained Egypt's president in an amateur video recording posted on the Internet.

"I am the elected president of Egypt," the Islamist politician said in the video uploaded to YouTube.

The Egyptian army toppled Islamist President Mohamed Morsi on Wednesday after a week of bloodshed that killed nearly 50 people as millions took to the streets to demand an end to his turbulent single year of rule.

The announcement, made on state television by Morsi's own defense minister, armed forces chief General Abdel Fattah al-Sisi, drew a rapturous welcome from the protesters who have camped out on the streets of Cairo for days.

Syrian President Bashar Assad has said that massive protests against his Islamist Egyptian counterpart has spelt the end of "political Islam," in statements posted on Wednesday on his official Facebook page.

"What is happening in Egypt is the fall of what is known as political Islam," Assad said in an interview with Syrian state newspaper Ath-Thawra, excerpts of which were posted on the Internet.

The United States said Wednesday it was "very concerned" about developments in Egypt's political crisis, and urged President Mohammed Morsi to "do more" to address the concerns of protesters.

"We do remain very concerned about what we are seeing on the ground in Egypt," State Department spokeswoman Jen Psaki said. "We feel there was an absence of significant steps laid out by President Morsi."

Egypt will overcome its current crisis if President Mohamed Morsi leaves office, Syria's Information Minister Omran al-Zohbi said on Wednesday, as massive protests against the Islamist leader went into their fourth day.

Egypt's "security and unity are a national responsibility", Zohbi told a news conference broadcast by state television.

A top aide to Egypt's President Mohammed Morsi slammed what he called a "military coup" on Wednesday as an army ultimatum passed and the security forces slapped a travel ban on the Islamist leader.

"For the sake of Egypt and for historical accuracy, let's call what is happening by its real name: Military coup," Essam al-Haddad, Morsi's national security adviser, said in a statement on Facebook.