BUDAPEST, Hungary — Prime Minister Gyurcsany of Hungary, under pressure to resign, and Budapest’s mayor urged police to crack down harder on protesters who have led two nights of rioting in the capital city.

The pleas during a joint press conference came after more than 250 people were injured in riots with police. Budapest Mayor Gabor Demszky, who is seeking a fifth term in October 1 municipal elections, called the rioters criminals and urged them to be “pushed off the streets.”

“I won’t be calm,” Mr. Demszky said at the press conference yesterday. “These extremist elements continued to wreak havoc on our city. They tried to occupy more public areas and to damage public institutions.”

The riots, the worst since the end of communism, were sparked by a leaked tape in which Mr. Gyurcsany confessed that the Socialist-led government misled the public about the need to cut spending before April general elections. He rejected calls to quit and pledged to continue his economic program and trim the deficit, the European Union’s largest compared with the size of its economy.

Mr. Gyurcsany three months ago announced measures, including higher taxes and increased prices for medicines, natural gas, and electricity, aimed at reducing the budget deficit. The shortfall is Europe’s largest compared with the size of the economy.

The measures were part of the reason people took to the streets, according to analysts including Gergely Hudecz of DZ Bank in Budapest. People are worried about their livelihoods and are angered by the contrast with Mr. Gyurcsany, one of the country’s richest men, he said.

“They have to pay the price of the austerity measures, and they have a very rich prime minister, and that’s very provocative,” Mr. Hudecz said.

About 50 people were taken to hospital in riots overnight, and 24 officers were injured as several hundred protesters lit fires and hurled stones at riot police. Mounted officers using flare guns, tear gas, and a water cannon dispersed the crowds by 4:45 a.m. and detained 98 people, Hungarian Police Chief Peter Gergenyi said.

About 200 protesters remained outside parliament yesterday, and the crowd was growing again throughout the day, as it did during the previous two days. Police were preparing for last night in the same way that they did Tuesday and are prepared for all eventualities, a spokesman, Peter Schon, said in a phone interview.

The previous two days were the worst street violence in Hungary since the end of communism in 1989. Though expressions of disappointment with the outcome of political change included the blocking of a bridge in Budapest four years ago, protests never led to violence.

Rioters invoked the memories on 1956, when Hungarians revolted against communist rule, fighting government and Soviet troops for weeks. Mr. Gyurcsany rejected the comparison, calling the events criminal acts, not a revolution.

The most violent rioters were known to the police, Magyar Hirlap reported, citing unidentified officials. The core was identified as supporters of Budapest soccer teams Ferencvaros and Ujpest, joined by members of right-wing groups Jobbik and the 64 Counties Movement, according to the newspaper.

In the first night of violence, about 200 people were injured as protesters stormed the headquarters of state television, burning cars and beating back a police attack.

The expletive-laden tape recording that sparked the protests was leaked to several journalistic outlets on September 17. Mr. Gyurcsany later published the full text in his Internet diary. He was calling for the start of a cleansing process in Hungarian politics, he said.

“We screwed it up, big time,” Mr. Gyurcsany said on the leaked tape of the meeting. “No country in Europe has been so blatant. We obviously lied throughout the past 1 1/2 to 2 years. And meanwhile, we didn’t do a thing for four years. Nothing.”

Last night’s crowd, estimated at tens of thousands by the news Web site Index, gathered outside parliament. Groups of bandanna-clad youths later broke off to head toward the Socialist Party headquarters and the radio building as the demonstration wound down.