Young people riding in vehicles smashed cars and store windows in suburban Sydney late Monday, a day after thousands of drunken white youths attacked people they believed were of Arab descent at a beach in the same area in one of Australia's worst outbursts of racial violence.

Sunday's attack — apparently prompted by reports that Lebanese youths had assaulted two lifeguards — sparked retaliation by young men of Arab descent in several Sydney suburbs, fighting with police and smashing 40 cars with sticks and bats, police said. Thirty-one people were injured and 16 were arrested in hours of violence.

The rampage on Monday broke out in Cronulla, the same coastal suburb where the violence began, and in neighboring Carringbah, said Paul Bugden, spokesman for New South Wales police. Calm was restored by early Tuesday.

Bugden said six people were arrested and one person apparently was hit by a rock in Monday's violence. He did not have descriptions of those involved in the rampage, but he said it "obviously stems from the last 24-48 hours."

Australian Associated Press, citing a resident who declined to be named, said men riding in up to 50 cars and wielding baseball bats converged on Cronulla, smashing cars. Ambulances were called to help at least one injured man seen lying on the side of the road.

Steven Dawson said a bottle thrown through his apartment window in the suburb of Brighton-Le-Sands showered his 5-month-old son Caleb with glass, but did not hurt the child.

Horst Dreizner said a car had rammed into his denture store and he feared the violence would escalate. "Personally, I think it is only the beginning," he said in a telephone interview.

Elsewhere, about 300 people of Arab descent demonstrated against Sunday's attack outside one of Sydney's largest mosques, amid tight security.

The riots began Sunday after rumors circulated that youths of Lebanese descent were responsible for an attack last weekend on two lifeguards at Cronulla Beach. Police said the assault was not believed to be racially motivated.

Police, meanwhile, formed a strike force to track down the instigators of the attack, some of whom were believed to be from white supremacist groups. Police said they were also seeking an Arab man who allegedly stabbed a white man in the back.

Morris Iemma, the premier of New South Wales state, said police would use video images and photographs to track down the instigators. "Let's be very clear, the police will be unrelenting in their fight against these thugs and hooligans," he said.

Prime Minister John Howard condemned the violence, but said he did not believe racism was widespread in Australia.

"Attacking people on the basis of their race, their appearance, their ethnicity, is totally unacceptable and should be repudiated by all Australians irrespective of their own background and their politics," Howard said.

But he added: "I'm not going to put a general tag (of) racism on the Australian community."

Australia has long prided itself on accepting immigrants — from Italians and Greeks after World War II to families fleeing political strife in the Middle East and Southeast Asia. In the last census in 2001, nearly a quarter of Australia's 20 million people said they were born overseas.

However, tensions between youths of Arabic descent and white Australians have been rising in recent years, largely because of anti-Muslim sentiment fueled by the Sept. 11, 2001, terror attacks in the United States and deadly bombings on the Indonesian island of Bali that killed 202 people, including 88 Australians, in October 2002.

About 300,000 Muslims live in Australia, the majority in large cities.

"Arab Australians have had to cope with vilification, racism, abuse and fear of a racial backlash for a number of years, but these riots will take that fear to a new level," said Roland Jabbour, chairman of the Australian Arabic Council.

Police had increased the number of officers patrolling the beach in the Sydney suburb on Sunday after cell phone text messages urged people to gather there to retaliate for the attack on the lifeguards.

Police said more than 5,000 white youths, some wrapped in Australian flags and chanting racist slurs, fought with police, attacked people they believed to be of Arab descent and assaulted a pair of paramedics trying to help people escape the riot.

Police fought back with batons and pepper spray.

Many of the youths had been drinking heavily, police said. One white teenager had the words "We grew here, you flew here" painted on his back. Someone had written "100 percent Aussie pride" in the sand. TV broadcasts showed a group of young women attacking another woman, whose ethnicity was not clear.

The violence shocked this city of 4 million that considers itself a cultural melting pot.

"What we have seen yesterday is something I thought I would never see in Australia and perhaps we have not seen in Australia in any of our lifetimes and that is a mass call to violence based on race," Community Relations Commission chairman Stepan Kerkyasharian told Sky News.

Cronulla Beach, which is easily accessible by train but is not a popular destination for foreign tourists, is often visited by youngsters from poorer suburbs, many of them of Arab descent. Residents accuse the youths of traveling in gangs and sometimes intimidating other beachgoers.

Aborigines rioted in the Sydney neighborhood of Redfern in February 2004 after blaming police for the death of a 17-year-old boy. Forty police were wounded.