By Elliott Gotkine
BBC News South America correspondent
Labour unions in Bolivia have vowed to continue their protests against the government after Congress rejected the resignation of President Carlos Mesa.
Mr Mesa's rejected resignation has not quelled opposition towards him
In a show of unity with indigenous groups, their supporters have stepped up road blocks across the country.
They have disrupted traffic and renewed fears of further instability in South America's poorest nation.
They are demanding foreign energy firms pay significantly higher taxes than the ones proposed by the government.
It was plans to export the country's gas that sparked a wave of deadly protests in October 2003 and resulted in President Mesa's predecessor being forced from office.
The rejection of President Carlos Mesa's resignation was supposed to usher in a period of calm and stability in Bolivia.
Instead, it appears to have energised his opponents.
In a rare show of unity, several leaders of Bolivia's indigenous majority joined forces.
Opposition lawmaker Evo Morales said they would now embark on a "face-to-face battle with the government" .
Phase one appears to be yet more roadblocks.
Bolivian television showed highways carpeted with boulders as Indian women wearing purple shawls and bowler hats sat in the road.
The protestors are demanding that the government raise the taxes levied on foreign energy firms from 15% to 50% of their sales.
President Mesa says that this would not be accepted by the international community.
In another development, the government has asked judicial authorities to arrest people impeding the free movement of traffic.
In the eastern province of Santa Cruz, several bus drivers were reportedly detained for blocking roads.
Counter-demonstrations are planned for Thursday.
President Mesa has called on Bolivians to pour onto the streets to show their opposition to the road blocks and protests which prompted his resignation in the first place.