Thousands of people took to the streets of Yemeni cities Saturday to protest the Shiite Houthi rebel takeover of the country's capital, Sana'a, earlier this week.

The protests in Sana'a and the country's third-largest city, Taiz, in southern Yemen, come just two days after Yemeni President Abd-Rabbu Mansour Hadi resigned, raising fears that the strategically located country would plunge further into chaos.

Footage from Taiz shows thousands of demonstrators at an anti-Houthi rally.

Al-Jazeera reported that up to 10,000 people marched in the capital from Sana'a University to former President Hadi's home, chanting against the Houthi group and al Qaeda. Young men, women and children reportedly carried signs demanding "a real government" and burned portraits of the Houthi leader Abdulmalek al-Houthi.

"Down, down with the Houthis' rule," the protesters chanted, according to AFP.

The news agency also reported that protesters took to the streets in the cities of Ibb and Hodeida. The protests were organized by the "Rejection Movement" — a group recently formed in provincial areas to challenge the Houthi movement.

In a move that could throw the country into further chaos, the governor and other senior officials in the southeastern region of Hadramout say they will reject all orders from the capital so long as the president and prime minister's offices remain empty, Al-Jazeera reported.

An Al-Jazeera correspondent in Aden said that the Southern Movement, a group that rejects Houthi rule, deployed its fighters to protect the port city from possible attack.

The Southern Movement "demands a return to the full independence that the southern region enjoyed from 1967 to 1990," and "had earlier raised the former flag of South Yemen over Aden's airport and a security headquarters building," the Al-Jazeera report said.

The Aden news site Adenalghad reported Friday that South Yemen secessionist leader Abd al-Rahman Ali al-Jafari had returned to the country. Adenalghad said crowds gathered at Aden International Airport to welcome his return.

Footage here shows Jafari's car making its way through a crowd. Jafari is the head of the South Arabian League.

The crowd in the video carries the secessionist South Yemen flag, which bears a blue triangle and red star. This was the flag of the former Communist People's Democratic Republic of Yemen, which was a separate country in Eastern and Southern Yemen until 1990, when North and South Yemen united under a single central government, based in Sana'a, called the Republic of Yemen.

In 1994, citing neglect from the central government of the unified Republic of Yemen, Jafari was one of the leaders of a renewed southern secessionist movement that sought to once again create an independent state in Yemen's south. These efforts led to a brief civil war between the central government and the secessionists that killed thousands of people.

The Houthis have also led uprisings against Yemen's central government since 2004 in an effort to attain greater autonomy for their northern Saada province. The Houthis follow a branch of Shia Islam called Zaidism, whose devotees comprise roughly 35 percent of Yemen's population. They feel they've been marginalized in the Sunni-majority country.

The Houthis took over government buildings in Sana'a earlier this week, surrounded the presidential palace, kidnapped the president's chief of staff and fired on the prime minister's car. The president and prime minister resigned Thursday, saying the Houthis had broken a peace and power-sharing deal brokered Wednesday.

BBC regional analyst Alan Johnston told the network that the resignation has created a sense that Yemen is "leaderless and drifting through a dangerously uncertain political moment."

The Middle East Institute's Charles Schmitz told the New York Times that "we're looking at the de facto partitioning of the country and we're heading into a long negotiating process but we could also be heading toward war."

"We are in uncharted territory now," said United Nations envoy to Yemen Jamal Benomar as he raised the possibility the country might break apart. "It's going to be very difficult days ahead."

The US State Department released a statement Thursday saying that the United States is "troubled by reports of President Hadi and his cabinet's resignation," and urged all sides to avoid violence.

"The people of Yemen deserve a clear path back to a legitimate, federal, and unitary Yemeni government… with clearly defined timelines to finish writing a new Yemeni constitution, to hold a referendum on this constitution, and to launch national elections," the statement said.