Authorities say there is no evidence that the attacks were coordinated but their timing in under 24 hours raises fears about security — already a major issue in the country’s deeply divisive presidential election battle between Hillary Clinton and Donald Trump.

Twenty-nine people were injured when a bomb exploded in New York’s upmarket Chelsea neighborhood on Saturday night, damaging buildings, shattering glass and sending shrapnel flying across the street.

A second bomb was uncovered by police four blocks away and defused safely, before being sent to the FBI in Virginia for forensic examination.

Both bombs were filled with shrapnel and made with pressure cookers, flip phones, Christmas lights and explosive compound, The New York Times reported late Sunday, citing law enforcement officials.

CNN reported that officials had obtained surveillance videos showing the same man near the site of the explosion and where the undetonated device was found, according to “multiple” local and federal law enforcement sources.

Hours earlier, less than 100 miles (160 kilometers) south in New Jersey, a pipe bomb exploded in a trash can on the route of a Marine Corps run before the start of the race, causing no injuries but forcing its cancellation.

In the Midwest, an assailant reported to be Somali-American went on a stabbing spree in a shopping mall in St. Cloud, Minnesota, injuring nine people before being shot dead by an off-duty police officer.

US authorities said the motive of all three attacks was unclear, but elected officials quickly identified them as terror-related.

“If you look at a number of these incidents, you can call them whatever you want: they are terrorism though,” New Jersey’s Republican Governor Chris Christie, a member of the Trump campaign, told CNN.

– Obama arrives in NY –

“A bomb exploding in New York is obviously an act of terrorism, but it’s not linked to international terrorism,” Democratic New York Governor Andrew Cuomo said Sunday after touring the scene of the explosion in Chelsea.

“In other words, we find no ISIS connection, et cetera,” said Cuomo in reference to the Islamic State group. But he also stressed the lack of an international terror link was preliminary.

New York went on full alert, deploying nearly 1,000 extra state police and National Guardsmen to airports, bus terminals and subway stations as President Barack Obama arrived in the city ahead of Tuesday’s opening of the UN General Assembly.

There was no claim for the bombings in Manhattan or New Jersey, but a jihadist-linked news agency, Amaq, claimed that an IS “soldier” carried out the Minnesota stabbings.

IS has repeatedly called for attacks on countries in the US-led coalition bombing the extremist group in Syria and Iraq.

“This should steel our resolve to protect our country and defeat ISIS and other terrorist groups,” said Clinton, using another acronym for IS.

The Democratic nominee, whose lead in the polls has taken a dip, condemned what she called “apparent terrorist attacks.”

Trump, who described the blast in New York a bombing more than 12 hours before officials or police, tweeted his “best wishes and condolences to all of the families and victims of the horrible bombing.”

In Minnesota, FBI agent Rick Thornton confirmed that federal agents were investigating the stabbing as “a potential act of terrorism,” as local media identified the suspect as a 22-year-old Somali-American.

– ‘References to Allah’ –

Police confirmed that the assailant asked some victims whether they were Muslim before attacking them and made “references to Allah.”

While all 29 people who were injured in the New York bombing have been released from the hospital, three of those hurt in Minnesota remain hospitalized, officials said.

“Was it a political motivation, a personal motivation? What was it?” New York Mayor Bill de Blasio said at a news conference. “We do not know,” he added, calling on residents to be vigilant.

Fifteen years after the September 11, 2001 attacks, officials stress that the United States is safer from terror plots that originate from overseas but more at risk from the lone-wolf attack perpetrated by individuals who may be inspired by IS or Al-Qaeda propaganda.

“In many of these cases we don’t know until two, three or four days later whether or not there is a terrorist link,” warned New York Congressman Peter King in a CBS television interview.

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