Joe Biden paid tribute to the first responders who assisted after the 9/11 attacks in a speech today, 11 September, remembering the victims.
On 11 September, 2001, Islamist extremists hijacked four planes, crashing into the Pentagon, the World Trade Center, and a field in Shankville, Pennsylvania, killing nearly 3,000 people.
The US president praised emergency service workers who helped clear rubble and search for victims from Ground Zero.
“Police officers and firefighters stood on the pile at Ground Zero for months... breathing in the toxins and ash... refusing to stop the search,” Mr Biden said.
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