One opponent said the law turned Hazleton into a "Nazi city"

Under the law, businesses and landlords in Hazleton could be penalised if they help illegal immigrants, and all city documents will be written in English.

The measure has divided the former coal town, which has seen a large rise in Hispanic residents in recent years.

Hundreds of people on both sides protested outside the City Hall.

Police officers were drafted in to prevent any trouble after the measure was approved in a 4-1 vote following a two-hour debate.

Mayor Lou Barletta proposed the law as a response to the city's problems with violent crime, demand for schools and services and hospital costs.

"What you see here tonight, really, is a city that wants to take back what America has given it," said Mr Barletta, who reportedly said he had worn a bullet-proof vest to the vote for fear of reprisals.

The illegal citizens, I would recommend they leave Mayor Lou Barletta

But one opponent outside the City Hall said it would make Hazleton "the first Nazi city in the country".

The measure means that landlords could be fined $1,000 (�544) for each illegal immigrant found renting their properties. Businesses who employ illegal immigrants could lose their operating licences.

Other US towns and cities have considered similar measures as Hazleton, which lies some 80 miles (130km) north-west of Philadelphia.

Similar local laws to tackle illegal immigration have been proposed in Florida's Palm Bay and Avon Park as well as the California towns of Escondido and San Bernardino, the Associated Press reports.