BUENOS AIRES, Argentina (AP) — Argentine President Cristina Fernandez said she wasn't intimidated by a nationwide strike led Tuesday by the union bosses who used to be her most steadfast supporters.

"No one makes me run away, much less with threats and bullying," she said, and dismissed the impact of the strike as minimal.

Many workers stayed home as the strike made commuting a puzzle, with some trains and bus lines paralyzed and small groups of people blocking highways in about a dozen places around the capital. Banks, courts and many schools were closed, many hospitals offered only emergency services, most Argentine flights were canceled and garbage wasn't being picked up.

But in other ways, it was a normal day in Buenos Aires, where cafes and small stores stayed open.

The strike was called as a political show of force by truckers' union boss Pablo Moyano, the longtime leader of Argentina's vast General Workers' Federation, and one of the closest allies of the president's late husband and predecessor, Nestor Kirchner.

Moyano and some other union leaders broke away from Fernandez this year as she tried to contain the demands of a now-divided labor movement by supporting a rival slate in union elections. He has increasingly appeared alongside her political opponents since then, speaking out against the government he long championed.

After his union members blocked hundreds of roads around the country, Moyano and other union leaders presented their demands, including "the total elimination of income taxes," and said Fernandez had lost control of the labor movement.

"I imagine that the sound on the streets, the lack of people walking around them, at shops and corporations, is the voice the government has to hear. That silence is the voice the government must hear," Moyano said.

Fernandez waved away such talk, saying that in a serious Argentine strike, "not even a fly can move."

Most union workers won pay hikes of 25 percent or more this year, in line with what private analysts say is Argentina's true annual inflation rate, much higher than the 10 percent a year cited by the government's widely discredited inflation index.

For most, those pay hikes put them over the threshold to begin paying income taxes, something many lower-paid workers never had to do before. For a single worker, that annual salary threshold is about $15,600. Tax rates then rise from zero to 35 percent, with most workers losing about a fourth of their take-home pay to income taxes.

"The government should stop robbing workers with the income tax," said the Workers' Party leader Nestor Pitrola, who joined a blockade of the Pueyreddon bridge over the Riachuelo river, a key access point from the south.

Most flights were grounded in Argentina, frustrating tourists at Buenos Aires' downtown airport, where machinists' union leader Ricardo Cirielli said 100 percent of the workers who maintain the jets of Aerolineas Argentinas and LAN Argentina were on strike. Other international carriers weren't affected, he said.