Unions opposed to Argentine President Cristina Fernandez's government brought the country to a standstill with a general strike on Thursday, while the administration said militants were preventing people from going to work.

The strike against "austerity, inflation and crime" was most disruptive in greater Buenos Aires because of the participation of the transport sector and protesters' blocking of main roads into the capital.

Strike organizers intend to cripple the main urban centers with the large-scale labor action, referring to the 40 roadblocks set up nationwide, Cabinet chief Jorge Capitanich told a press conference.

"The right to strike is a right enshrined in the constitution and its use seems to me to be perfectly legitimate," but "what's not allowable is to impede the free exercie of that right," he said.

"There are workers who are not in agreement (with the strike) and they are unable to get to their workplaces," Capitanich said.

Since dawn, protesters had blockaded roads leading into the capital, most notably the Pan American Highway, where clashes between police and demonstrators left two injured and one arrested.

Commuter rail and bus service was paralyzed.

"The strike has been a success from the outset," labor leader and congressman Nestor Pitrola said, adding that "a new stage has been launched" in the unions' struggle, "which began with the teachers strike and continues with this strike that seeks to define where the country is heading."

The CGT labor federation's dissident faction - headed by Hugo Moyano, a one-time close Fernandez ally who is now a staunch government opponent - organized the general strike, the second Fernandez has faced since taking office in December 2007.

The unions are demanding salary hikes of more than 40 percent and an increase in the level of earnings exempt from income tax, which now stands at 15,000 pesos ($1,875). EFE