La Paz, Bolivia ? Vice President Carlos Mesa took office as Bolivia’s new president late Friday but quickly proposed having early elections, hours after his predecessor was forced out by weeks of bloody street protests set off by a plan to export natural gas to the United States.

Gonzalo Sanchez de Lozada stepped down when he lost the support of his last key ally and his beleaguered government collapsed, sparking widespread celebrations in the streets.

Congress, in emergency session, accepted the 73-year-old leader’s resignation and quickly named Mesa to the top post. As vice president, Mesa was next in the line of succession.

Wearing the red, yellow and green presidential sash, Mesa addressed lawmakers, calling for unity for solve the country’s worst crisis since Bolivia returned to democracy in 1981.

“I’m taking office at a crucial time in Bolivia’s history. … My first obligation is to listen to what the thousands of people have said during the last few weeks,” he said, referring to the demonstrators who have marched throughout the country since late September. More than 65 people were killed in rioting.

Mesa, a former television reporter and a respected historian, is a political independent, and it wasn’t immediately clear how much political support he will have. It also wasn’t known how long he will serve.

Thousands of miners celebrate at the plaza de los Heroes in downtown La Paz, Bolivia, after hearing rumors of Bolivian President Gonzalo Sanchez de Lozada's resignation. De Lozada stepped down Friday, permitting his vice president, Carlos Mesa, to take power.