United States prosecutors slapped the gunman who killed 11 people in a synagogue with 29 counts of federal crimes of violence and firearms offenses on Saturday, after he carried out the deadliest anti-Semitic attack in recent U.S. history.
Ambassador Dayan represents Israel in five states, including Pennsylvania.
Worshippers "were brutally murdered by a gunman targeting them simply due to their faith", said Bob Jones, head of the FBI's Pittsburgh office, though he cautioned the shooter's full motive was not yet known.
"In reality, all of us are wounded by this inhuman act of violence", he said.
The mass killing is being investigated as a federal hate crime. "We will continue to thrive and sing and worship and learn together and continue our historic legacy in this city with the friendliest people that we know".
KDKA television cited police sources as saying Bowers walked into the building and yelled, "All Jews must die".
This is the kind of attack-no, these are the kinds of attack-that call for the strongest, most powerful, most unequivocal unity of all those who face racist, anti-Semitic, xenophobic, Islamophobic, homophobic, misogynistic, transphobic violence, a unity to bring down the forces of white supremacy and hate.
Many Americans believe that the increase in anti-Semitism, xenophobia and racism over the past two years has been stoked by the rhetoric of some of the nation's top leaders, particularly President Trump, whose ongoing rallies are marked by denunciations of immigrants and the deriding of "globalists", which is viewed as a code word for Jews.
Bowers, who underwent surgery and remained hospitalized, is scheduled for a court appearance Monday.
On Sunday, US authorities released the names of the 11 victims killed by suspected gunman Robert Bowers, including a husband and wife couple, and two brothers. Her father, Alex Lindenauer said talking to his children about the Pittsburgh tragedy was "difficult but necessary". One of those is critically wounded, but the condition of the fourth is not known.More news: Volkswagen T-Cross: new SA-bound baby crossover revealed!
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Authorities say that just before 10 a.m., Bower entered the large synagogue with an assault-style rifle and three handguns. He has been charged with 29 counts, including 11 of murdering people exercising their religious beliefs, which carry a death penalty if he is found guilty. "Screw your optics, I'm going in", he posted.
Scott Brady, from the Federal Bureau of Investigation, said they would do everything to ensure Bowers was held accountable for his actions.
The mass shooting sparked security alerts at houses of worship around the country and condemnation from politicians and religious leaders.
The shooting came amid a rash of high-profile attacks in an increasingly divided country, including the series of pipe bombs mailed over the past week to prominent Democrats and former officials.
The suspect, Robert G. Bowers, 46, a resident of Baldwin, in the Pittsburgh metropolitan area, was taken into custody following an exchange of gunfire with police officers who had arrived on the scene of the attack at the Tree of Life Synagogue in the Squirrel Hill neighbourhood. He said Saturday that "if there was an armed guard inside the temple, they would have been able to stop him".
Around the time, three congregations amounting to about 100 people would have been using the building, Mr Eisenberg said.
The Anti-Defamation League, which has monitored anti-Semitism in the USA for more than a century, said Sunday that the mass shooting "was the deadliest anti-Semitic attack in US history".
Hissrich said extra patrols have been assigned to "sensitive locations around Pittsburgh", including at a vigil planned for Sunday night.
Other vigils were held across Canada including in Montreal, Halifax and Vancouver. He eventually surrendered and was taken to the University of Pittsburgh Medical Center for a gunshot wound, which could either have been self-inflicted or caused by police.