PLEASE NOTE: EDIT CONTAINS MATERIAL THAT WAS ORIGINALLY 4:3
The prospect of a deal to develop a massive shale oil and gas field in Argentina is generating a lot of heat in the province where it lies.
So much so that this protest against the possible deal to exploit the vast resources turned violent.
Police fired tear gas and rubber bullets under a hail of rocks and petrol bombs from the protesters.
About 5, 000 demonstrators turned out to show their opposition to a tie-up between Argentine energy firm YPF and U.S.-based Chevron.
The government recently eased petroleum sector rules enabling the deal worth nearly one and quarter billion dollars to go ahead.
(SOUNDBITE)(Spanish) UNIDENTIFIED PROTESTER, SAYING:
"This is the government of Cristina Fernandez de Kirchner with the complicity of the provincial governor. This is the answer they give to the people who say no to pollution, sons of bitches."
Those who oppose the development of the Vaca Muerta field face a major battle.
Argentina is counting on the field to regain the energy self-sufficiency it lost a decade ago, costing millions of dollars to import supplies as a result.