Sydney, Austrailia ? Violence spilled into a second night Monday as scores of youths drove through predominantly white suburbs of Sydney, smashing windows of cars, homes and stores and raising fears of spreading racial unrest.

Prime Minister John Howard called the violence “sickening,” but denied it was rooted in racism. Arab community leaders said the unrest would heighten racial tensions as cell phone text messages warned of retribution by the Arab community and attacks by neo-Nazi groups.

About 5,000 white men, many of them drunk, targeted people believed to be of Arab or Middle Eastern descent on Cronulla Beach on Sunday after rumors spread that Lebanese youths assaults two lifeguards earlier this month.

Police, who had stepped up patrols on the beach after learning of cell phone text messages urging people to retaliate for the attack on the lifeguards, fought back with batons and pepper spray.

Young men of Arab descent struck back in several Sydney suburbs Sunday, fighting with police for hours and smashing dozens of cars with sticks and bats, police said. They said 31 people were injured, including a white man who was allegedly stabbed in the back, and 16 arrested.

Carloads of youths also tore through the suburbs Monday night, attacking vehicles and throwing bottles through windows. While only one person was reported injured and six arrested, there appeared to be more damage to cars and stores than on Sunday.

Images of Sunday’s riot shocked Australians, who pride themselves on tolerance and credit an influx of immigrants with helping build up the country after World War II.

A New South Wales police officer, back to camera, attempts to clear youths from a train who were attacking another youth after ethnic tensions erupted into running battles between police and a mob of thousands of youths, many chanting racial slurs. Violence on the streets of Sydney spilled into a second night Monday as scores of youths drove through beachside suburbs smashing windows of stores, homes and apartments, police said.

Tensions between youths of Arabic and Middle Eastern descent and white Australians have been rising in recent years, fueled by the 9-11 attacks in the United States and deadly bombings on Bali that killed 202 people, including 88 Australians.

Many Muslims also were angered over Howard’s decision to contribute troops to the U.S.-led invasion of Iraq in 2003.

The president of the Islamic Friendship Association of Australia, Keysar Trad, said the violence was “bound to happen” following angry calls to radio talk shows after the attack on the lifeguards. Police have denied the assault on the lifeguards was racially motivated.

Police spokesman Paul Bugden said he did not have descriptions of those involved in Monday night’s rampage, but said it was linked to Sunday’s rioting.

Witnesses told an Associated Press photographer that some youths involved in the attacks were Middle Eastern or Arabic in appearance and others wore ski masks. Australian Broadcasting Corp. reported that police said men of Middle Eastern appearance were involved.

In the 2001 census, nearly a quarter of Australia’s 20 million people said they were born overseas. The country has about 300,000 Muslims, most in lower income suburbs.