Officials in Yemen's second-largest city say gunmen have killed four soldiers near the presidential palace. Officials say one of the attackers also was killed in the violence Sunday in Taiz.

The assault comes a day after Yemen's authoritarian president left the country to receive medical treatment in Saudi Arabia.

Thousands of anti-government protesters in Sana'a on sunday celebrated President Ali Abdullah Saleh's departure. They are hoping that Mr. Saleh's departure is permanent, bringing an an end to his 33-year reign.

Yemeni Vice President Abed Rabbo Mansour Hadi met with U.S. Ambassador Gerald Feierstein Sunday, a strong indicator that Hadi is in charge since the president's departure. U.S. officials also say President Barack Obama's national security adviser, John Brennan, spoke with Hadi Saturday.

President Saleh and at least four other high-ranking officials flew to neighboring Saudi Arabia Saturday after they were wounded in an attack Friday on the presidential compound in Sana'a.

However, the extent of Mr. Saleh's injuries were not immediately clear and it is not known whether the president intends to return to Yemen.

One of Mr. Saleh's sons who commands the powerful presidential guard and two of the president's nephews remain in Yemen, suggesting that the president's departure will not necessarily end the country's crisis.

Yemeni government officials and rebel tribesmen agreed to a new cease-fire Saturday brokered by Saudi Arabia.

Representatives of both sides said they will accept the plan. Just a week ago, a similar truce quickly collapsed in renewed fighting between President Saleh's forces and loyalists to an opposition tribal leader, Sheikh Sadiq al-Ahmar.

Nearly 400 people have been killed since the popular uprising against Mr. Saleh began in January.