Several thousand Hungarians have been demonstrating in Budapest this week after Prime Minister Viktor Orban's government fast-tracked legislation sharply raising taxes for small firms.

Protesters hit the streets of the Hungarian capital for the third day on Thursday, camping out on a bridge in the city center to show their anger about the changes. 

They were joined by a heavy police presence, attempting to keep traffic flowing over the Erzsebet Bridge.

Protests kicked off on Tuesday when the government rushed through new legislation through parliament that will change tax rules for freelance workers and small business owners. 

Many of them say the changes, which take effect in September, will drastically reduce their income. The government argues that the current system has been taken advantage of, insisting the rules needed to be tightened up. 

On Tuesday, protesters blocked entirely a major bridge in central Budapest, preventing cars and trams from crossing for most of the day. 

The next day, thousands of demonstrators gathered outside the parliament building before marching through the streets and taking over the major Oktogon intersection. They then moved around the city until the early hours of the morning, followed by large numbers of police. 

These are the first major demonstrations since Prime Minister Viktor Orban was re-elected in April. The early months of his new term in office have seen rising inflation and the Hungarian currency, the forint, hitting record lows against the euro. 

In addition to widespread anger about the tax legislation, there are signs that the protesters' demands are widening. 

On Wednesday, the government announced that a longstanding cap on utility prices for some households will be scrapped. The move is part of a wider "state of emergency in energy" declared by the authorities this week. 

"Wastefulness can no longer be afforded anywhere," said Gergely Gulyas, chief of staff to the Prime Minister. "Every alternative should be looked at that provides incentives for the most sparing use of energy in the economy."

In response, there are now calls for wider demonstrations against the ruling Fidesz party on Friday.