by Hannah Strange

Barack Obama's election as America's first black president has unleashed a wave of hate crimes across the nation, according to police and monitoring organisations.

Far from heralding a new age of tolerance, Mr Obama's victory in the November 4 poll has highlighted the stubborn racism that lingers within some elements of American society as opponents pour their frustration into vandalism, harassment, threats and even physical attacks.

Cross burnings, black figures hung from nooses, and schoolchildren chanting "Assassinate Obama" are just some of the incidents that have been documented by police from California to Maine.

There have been "hundreds" of cases since the election, many more than usual, said Mark Potok, director of the Intelligence Project at the Southern Poverty Law Center, which monitors hate crimes.

The phenomenon appears to be at its most intense in the Southern states, where opposition to Mr Obama is at its highest and where reports of hate crimes were emerging even before the election. Incidents involving adults, college students and even schoolchildren have dampened the early post-election glow of racial progress and harmony, with some African American residents reporting an atmosphere of fear and inter-community tension.

In North Carolina, four students at the state university admitted writing anti-Obama comments in a tunnel designated for free speech expression, including one that said: "Let's shoot that (N-word) in the head." Mr Obama has received more threats than any other president-elect, authorities say.

Marsha L. Houston, a University of Alabama professor, said a poster of the Obama family was ripped off her office door. A replacement poster was defaced with a death threat and a racial slur. "It seems the election brought the racist rats out of the woodwork," Ms Houston said.

Second and third-grade students on a school bus in Rexburg, Idaho, chanted "assassinate Obama," a district official said.

Meanwhile in Snellville, Georgia, Denene Millner, an African-American, said a boy on the school bus told her nine-year-old daughter the day after the election: "I hope Obama gets assassinated." That night, someone trashed her sister-in-law's front lawn, mangled the Obama lawn signs, and left two pizza boxes filled with human faeces outside the front door, Ms Millner said.

She described her emotions as a combination of anger and fear.

"I can't say that every white person in Snellville is evil and anti-Obama and willing to desecrate my property because one or two idiots did it," Ms Millner said. "But it definitely makes you look a little different at the people who you live with, and makes you wonder what they're capable of and what they're really thinking."

But the incidents have not been restricted to areas of high anti-Obama sentiment. Even states and cities which leaned heavily towards the Democrat have seen their share.

In New York, a black teenager said he was attacked with a bat on election night by four white men who shouted "Obama", while in the Pittsburgh suburb of Forest Hills, a black man said he found a note with a racial slur on his car windshield, saying "now that you voted for Obama, just watch out for your house."

In the north-eastern state of Maine, customers at a general store in Standish were placing $1 bets on when the president-elect would be killed. A sign inside the Oak Hill General Store read: "Osama Obama Shotgun Pool." "Stabbing, shooting, roadside bombs, they all count," it said. At the bottom of the marker board was written "Let's hope someone wins."

Black figures were hung by nooses from trees on Mount Desert Island, Maine, the Bangor Daily News reported, while crosses were burned in yards of Obama supporters in Hardwick, New Jersey, and Apolacan Township, Pennsylvania. In Massachussetts, a nearly-finished church belonging to a black congregation was burned to the ground just hours after Mr Obama's victory was declared.

Racist graffiti was found in places including New York's Long Island, where two dozen cars were spray-painted; Kilgore, Texas, where the local high school and skate park were defaced; and the Los Angeles area, where swastikas, racial slurs and "Go Back To Africa" were spray painted on sidewalks, houses and cars.

Mr Potok, who is white, said he believes there is "a large subset of white people in this country who feel that they are losing everything they know, that the country their forefathers built has somehow been stolen from them."

Grant Griffin, a 46-year-old white Georgia native, expressed similar sentiments: "I believe our nation is ruined and has been for several decades and the election of Obama is merely the culmination of the change.

"If you had real change it would involve all the members of (Obama's) church being deported," he said.

Change in whatever form does not come easy, and a black president is "the most profound change in the field of race this country has experienced since the Civil War," said William Ferris, senior associate director of the Center for the Study of the American South at the University of North Carolina. "It's shaking the foundations on which the country has existed for centuries."

"Someone once said racism is like cancer," Mr Ferris said. "It's never totally wiped out - it's in remission."

The day after the vote, Barbara Tyler, a black high school student in Marietta, Georgia, said she heard hateful comments about Mr Obama from white students, and that teachers cut off discussion about his victory.

Ms Tyler spoke at a press conference by the Georgia chapter of the civil rights body NAACP which discussed complaints from across the state about hostility and resentment. Another student, from a Covington middle school, said he was suspended for wearing an Obama shirt to school on November 5 after the principal told students not to wear political paraphernalia.

The student's mother, Eshe Riviears, said the principal told her: "Whether you like it or not, we're in the South, and there are a lot of people who are not happy with this decision."

Sociologists said African-Americans suffering attacks and intimidation were essentially proxies for the frustrated emotions of some whites.

"The principle is very simple," said BJ Gallagher, a sociologist and co-author of the diversity book 'A Peacock in the Land of Penguins.' "If I can't hurt the person I'm angry at, then I'll vent my anger on a substitute, i.e., someone of the same race."

"We saw the same thing happen after the 9-11 attacks, as a wave of anti-Muslim violence swept the country. We saw it happen after the Rodney King verdict, when Los Angeles blacks erupted in rage at the injustice perpetrated by 'the white man.'

"It's as stupid and ineffectual as kicking your dog when you've had a bad day at the office," Mr Gallagher said. "But it happens a lot."