Ousted Syrian President Bashar Assad flees to parts unknown as rebels declare country is 'free of the tyrant'

The possible whereabouts of ousted Syrian President Bashar al-Assad began to emerge Sunday after he abruptly resigned and fled Damascus as rebel forces stormed the capital and declared victory over the man they described as a "tyrant."

The 59-year-old Assad boarded a plane in Damascus on Sunday morning and flew to an unknown destination as the rebels overthrew the government and seized power, ending Assad's iron-fisted 24-year reign.

Russian state media reported Sunday that Assad and his family are now in Moscow, but there has been no official confirmation from the Kremlin that it had reportedly offered Assad refuge.

"Assad and his family members arrived in Moscow," Russia's TASS news agency reported, citing an unnamed Kremlin source who told TASS the Kremlin has provided Assad and his family asylum.

In a speech from the White House on Sunday afternoon, President Joe Biden said, "Rebel forces have forced Assad to resign his office and flee the country."

"We're not sure where he is, but there's word he's in Moscow," Biden said.

When answering a reporter's question about what should happen to Assad, Biden paused before leaving the Roosevelt Room, responding, "Assad should be held accountable."

In his address, Biden said the Assad regime had "brutalized and tortured and killed literally hundreds of thousands of innocent Syrians" during the country's 13-year civil war.

Assad's hasty departure from Damascus caught his close advisers off guard.

Syrian Prime Minister Mohammad Ghazi al-Jalali said during an interview with a Saudi news channel on Sunday that while he has spoken with Assad since Saturday, he claimed he did not know his location.

The prime minister said he would work with the rebel leaders on a smooth transition to power.

The rebels, which operate under the military command of the Islamist Hayat Tahrir al-Sham group (HTS), moved into the capital and occupied the presidential palace.

"We declare the city of Damascus free of the tyrant Bashar al-Assad," HTS said in a statement.

A Syrian opposition fighter was photographed Sunday sitting inside an office at the Presidential Palace after the Syrian government collapsed.

HTS also said that all "unjustly detained persons from the regime's prisons have been released."

Video emerging from Syria showed civilians pouring into the streets of Damascus and Aleppo, where the rebel uprising began last week, celebrating and shooting off fireworks as word that the Assad regime had been toppled spread across the country.

The Russian Foreign Ministry said in a Sunday morning statement that Assad "decided to leave the presidential post and left the country, giving instructions to transfer power peacefully."

Assad agreed to give up power as the result of negotiations between him and the rebels, according to the Russian Foreign Ministry, which added that Russia did not participate in the negotiations.

Russian officials have declined to say whether the Kremlin has offered Assad a refuge in Russia.

In its first official reaction, Iran's Foreign Ministry said, "The future of Syria is only decided by the people."

"The relations between the two nations of Iran and Syria have a long history and have always been friendly, and it is expected that these relations will continue with the wise and far-sighted approach of the two countries based on common interests and benefits and compliance with international legal obligations," the Iranian Foreign Ministry said in its statement. "The Islamic Republic of Iran, emphasizing Syria's position as an important and influential country in the West Asian region, will spare no effort to help establish security and stability in Syria, and to this end, it will continue its consultations with all influential parties, especially in the region."

Speaking at a defense conference earlier in the day, before rebels advanced into Damascus, U.S. National Security Adviser Jake Sullivan said the speed and scale of the rebels' rapid advance came, in part, because Iran, Russia and Hezbollah had all been "weakened and distracted" in recent months.

That had left Assad "basically naked," Sullivan said at the Reagan National Defense Forum in California. "His forces are hollowed out."