BUENOS AIRES, Argentina - Police and national guardsmen fired tear gas at jobless workers Wednesday as demonstrators protesting against the economic crisis attempted to blockade highways around the capital.

There was no immediate report on injuries during the brief outburst of violence, in which police also fired rubber bullets to disband approximately 200 jobless protesters at one of the protest sites.

The violence erupted just before midday as police confronted the demonstrators near the Pueyrredon bridge, a key highway artery connecting the capital's north and south.

Masked demonstrators responded to the volleys of police tear gas and rubber bullets with a hail of rocks. The protests also used homemade clubs to shatter shop windows and smash cars. One bus was also set on fire and an unspecified number of arrests were reported before police restored order and traffic resumed.

The demonstrations came on a day when jobless picketers also blocked other access routes to the capital, defying government vows to crack down on any demonstrators who snarl traffic leading into or out of the capital.

Reports said police and guardsmen also broke up an attempt to blockade a highway north of the capital by picketing protesters who are demanding government food assistance and jobs. No violence was reported there.

The caretaker government of President Eduardo Duhalde had warned protesters in recent days to exercise restraint, warning it would not hesitate to use force to maintain public order.

Road blockades and protests against the government's handling of a protracted recession have become near daily events across Argentina since the crisis exploded last December into street riots that claimed 29 lives.

Since January, the country has devalued its currency more than 73 percent against the dollar, defaulted on its dlrs 141 billion public debt and seen billions of dollars in international aid shut off.

Meanwhile, Economy Minister Roberto Lavagna was scheduled to meet later Wednesday in Washington with officials of the International Monetary Fund ( news - web sites) in hopes of a resumption of bailout aid.

Local reports said an IMF advance team had raised numerous questions about the government's ability to provide a satisfactory recovery plan. Argentina is reportedly seeking as much as dlrs 20 billion in aid.

On Wednesday, lines again formed at banks as jittery peso holders sought to buy dollars. The peso was valued for 11 years at 1 to 1 with the dollar until a January devaluation. The local currency has been ebbing in value for months, falling this week to nearly 4 pesos to every dollar.