The confrontation centered on whether airlines should pay fees to the local government or national airport authority, but was driven by underlying tensions over the local government's attempts to carve more autonomy from President Evo Morales' socialist federal government, Mercopress reported Saturday.

The left-leaning Morales sent 220 troops to the airport Thursday and used tear gas when protesters showed up. But Friday, the troops withdrew without confronting the demonstrators, who shouted "This is ours" and waved flags as they stood on the runway and occupied airport hallways, the news agency said.

Ruben Costas, governor of Santa Cruz, said the soldiers left "with their tails between their legs."

However, Morales went on TV to say he ordered the troops to withdraw to prevent violence. At least two soldiers were wounded Thursday and hospitals reported another 20 people were injured.

The airport is located in Bolivia's richest and most pro-business province.