Appearing in Philadelphia on Monday, President Joe Biden addressed the situation in Springfield, condemning what he called the “lies and hate”.
“It’s wrong. It’s simply wrong. And it must stop,” he said.
Two colleges in Springfield held classes virtually on Monday. Wittenberg University said it received two threats over the weekend, “both of which were targeted toward members of the Haitian community”.
Clark State College said it would operate virtually through Friday “due to recent events in Springfield”.
Springfield City Hall, several schools, and state motor vehicle offices were forced to evacuate last week after receiving bomb threats.
Thousands of Haitian immigrants have settled in recent years in the predominantly white, blue-collar city of about 60,000, about 70 kilometres from the state capital of Columbus, where they have found work in factories and warehouses that had been struggling to fill job openings.
The sudden influx has strained schools, healthcare facilities and city services and driven up the cost of housing.
The surge of rumours directed at Springfield comes as suspicious packages were sent to election officials in at least five states.
There were no reports that any of the packages contained hazardous material.
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Powder-containing packages were sent to secretaries of state and state election offices in Iowa, Nebraska, Tennessee, Wyoming and Oklahoma, officials in those states confirmed on Monday (US time).
The FBI and US Postal Service were investigating. It marked the second time in the past year that suspicious packages were mailed to election officials in multiple state offices.
The latest scare comes as early voting has begun in several states less than two months ahead of the high-stakes elections for president, Senate, Congress and key statehouse offices around the nation, causing disruption in what is already a tense voting season.
Several of the states reported a white powder substance found in envelopes sent to election officials. In most cases, the material was found to be harmless.
AP, with Chris Zappone
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