The situation in Yemen is at its most volatile, according to those keeping a close watch.
At least two people have been killed and 15 wounded by a grenade attack in Sanaa, the capital.
Sources say the target was an army general who had backed opposition calls for President Ali Abdullah Saleh to resign.
There are also reports of heavy fighting in the southern city of Taiz.
Saleh has flown to Saudi Arabia for medical treatment following a bold attack on his compound.
He was praying in a mosque in his palace on Friday when it was hit by either rockets or a bomb. The vice president is said to be now in charge.
News of Saleh’s temporary departure was met with joy on the streets, though it is not clear yet if this marks the end of his rule. Experts predict two possible scenarios: either a violent power grab to fill the vacuum or a face-saving agreement allowing Saleh to transfer power.