A televised statement said the group was forming a presidential council that would run the country. It called the takeover "a new era that will take Yemen to safe shores."
A prominent presence in the Al-Qaida in Yemen organization, Sheik Harith al-Nadhari was among those who praised the recent attack on French magazine Charlie Hebdo.
The strikes come just days after Yemen's the U.S.-backed government resigned in the face of an uprising by Shiite Houthi rebels, effectively leaving the country with no government.
The Houthis have burst onto the scene in recent months and effectively taken control of the capital, Sanaa. Members espouse an offshoot of Shiite Islam and are now a major force in a volatile country.
The Houthis, who control the capital, Sanaa, are apparently hoping to exploit a power vacuum left by the resignation of President Abed Rabbo Mansour Hadi and his government.
The resignations compound a political crisis that began earlier this week when Shiite Houthi rebels took control of much of the capital, Sanaa, and surrounded the president's residence.
The agreement, which would see the rebels withdraw from parts of the capital in exchange for concessions, could defuse a political crisis that has threatened the stability of a key U.S. ally.
Yemen has once again been plunged into chaos as rebels reportedly have taken the presidential palace. The U.S., Saudi Arabia and Iran all have an important stake in the troubled country.
The Associated Press is calling the "shelling ... a dramatic escalation in the violence that has gripped Sanaa since Monday." Some Yemeni officials are calling the rebels' move "a coup."
President Abed Rabbo Mansour Hadi's chief of staff was kidnapped from his car in the heart of the capital Sanaa. Security officials blame Houthi rebels.