The State Department confirmed Friday morning that at least two Americans are among the dead in the Nice, France Bastille Day attack.

State Department spokesman John Kirby did not name the two victims, but friends on social media identified them as father and son Sean and Brodie Copeland of Lakeway, Texas.

Sean, a 51-year-old Lexmark Corporation executive, and his 11-year-old son were watching the Bastille Day fireworks on the Nice waterfront on Thursday when a terrorist drove a truck through the crowds and opened fire - killing at least 84.

A family friend said that Mr Copeland's wife Kim, 39, and his two adult children from another marriage, 21-year-old Austin and 29-year-old Maegan, 'witnessed the horrible tragedy but were able to get out of harm's way'.

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Father and son Sean, 51 (right), and Brodie Copeland have been named as the two Americans killed in the Nice, France terror attacks. Eleven-year-old Brodie is pictured on the left playing in the sea in a photo sent to a friend the day of the attack

The father and son were on a family vacation with Mr Copeland's wife Kim, 39 (right), and his two adult children from a prior relationship, 29-year-old Maegan (second left) and 21-year-old Austin (second right)

'My heart aches right now. Lost a really good friend and his son in the Nice, France terror attack. Please pray for the Copeland family. Especially for Kim, Austin and [Maegan] as they witnessed the horrible tragedy but were able to get out of [harm's] way. I know both Sean and Brodie knew and loved Jesus and that is comforting but it still hurts to the core,' friend Jason Granger wrote on Facebook.

Another family friend, Jess Davis, told the Texas Statesman that the Copelands and their three children were on a family vacation 'when this unthinkable and unfair act of terror took Sean and Brodie from the world far too soon'.

'We are heartbroken and in shock over the loss of Brodie Copeland, an amazing son and brother who lit up our lives, and Sean Copeland, a wonderful husband and father. They are so loved,' the Copeland family said in a statement issued through Davis.

The family reportedly started their vacation in Pamplona before journeying on to Barcelona and Nice. Adult children Maegan and Austin pictures above at the Running of the Bulls in Pamplona last week

Family friend Jason Granger says Kim Copeland and her two step-children witnessed the horror but were able to escape to safety

The family of five started their journey in Pamplona, Spain then continued on to Barcelona before crossing the border into France to celebrate Bastille Day in Nice.

Eldest child Maegan, a technical recruiter for Uber, posted a picture on Instagram of her and her brother Austin, a Texas State University senior, dressed in white for the Running of the Bulls in Pamplona last week.

We are heartbroken and in shock over the loss of Brodie Copeland, an amazing son and brother who lit up our lives, and Sean Copeland, a wonderful husband and father. They are so loved. Statement from the Copeland family

Mr Copeland, an alumni of the University of North Texas in Denton, was the vice president of North and South America for Lexmark Corporation's Kapow Software Division. He also served as an administrator on his youngest son's baseball team.

Relative Haley Copeland wrote on Facebook Friday morning: 'By now many of you have heard about the 80 people that have died in Nice, France today from a terrorist attack driving through a parade.

'[Two] of those 80 people were American and those 2 people happen to be uncle Sean and 11 year old cousin Brodie. They were there on vacation with my two other cousins and aunt celebrating a birthday.

'This is an extremely difficult time for my family and anyone who knows Sean and Brodie Copeland. Losing a loved one is hard no matter the circumstances but losing a loved one in such a tragic and unexpected way is unbearable. Prayers are much appreciated. #CopelandFamily #nice.'

Sean was believed to be taking part in a 'dream holiday' to the Riviera when he was killed by terrorists believed to be affiliated with ISIS. His son Brodie is pictured on the left in his baseball portrait. Father and son pictured on the right after a trophy ceremony

Relative Haley Copeland was one of the victims' family members to confirm their deaths online after the attack

Hill Country Baseball, where Brodie was a player, messaged saying: 'This evening we would like to ask that the HC family keep the Copelands in your prayers.

'This afternoon our very own Brodie Copeland, as well as his father Sean Copeland, were killed during the terrorist attack in Nice, France.

'Nobody deserves this type of fate, especially not such a wonderful family. You are in our hearts, thoughts, and prayers. Rest in peace, Brodie and Sean, you will be remembered by many.'

Friends of the family paid tribute to the father and son on Facebook following their deaths on Thursday night.

Victor Flores wrote: 'I'm in complete shock! Some of the best people I've had the privilege to know. You will definitely be missed Sean and Brodie.

'Kim, I do not have the words nor know what you are going through. I'm truly sorry for your loss. On behalf of Gio and the rest of my family, we love you!’

Jeff Petry said the father and son ‘touched our lives in so many ways’, adding: ‘No words can describe how we feel. Such a good man and a great kid and teammate.’

Joshua Sanders wrote: ‘Just terrible news. Kim and family are in our prayers. Brodie was such a lovely young man, and Sean an equally great guy.’

A fund has been set up to benefit the family on Go Fund Me. As of Friday afternoon, the fund had raised over $15,000.

Friends paid tribute to the father and son (pictured), saying they were 'some of the best people I've had the privilege to know' who 'touched our lives in so many ways'

The Copeland children pictured from left to right in a photo from 2014: Austin, Brodie and Maegan

Another 18 people are believed to have been seriously injured as attackers, thought to be affiliated with ISIS, drove a truck packed with weapons and explosives into holiday crowds.

One eyewitness described seeing 'bodies flying like bowling pins' and 'hearing noises, cries that I will never forget' as the horror unfolded on a busy promenade at around 11pm last night.

Secretary of State John Kerry's office confirmed that two Americans were dead in the attack from Moscow, where he is speaking with his Russian counterpart this week about Syria.

'At this time, we are aware of and can confirm two US citizens were killed in the attack in Nice on July 14, 2016,' State Department spokesman Kirby said in a statement.

'We express our sincere condolences to the family and friends of those killed.'

Kirby added that the State Department is providing 'all possible consular assistance' to its citizen.

Kirby's announcement came after President Barack Obama strongly condemned what he said was a 'horrific terrorist attack' and said the United States stood 'in solidarity and partnership with France'.

'Our embassy in Paris is making every effort to account for the welfare of US citizens in Nice,' Kirby said. 'Any U.S. citizens in Nice should contact friends and family directly to inform‎ them of their well being.'

At least 80 people have died and another 18 are reported to be severely injured after attackers, believed to be affiliated with ISIS, drove a truck packed with explosives into crowds celebrating Bastille Day

Vice President Joe Biden issued a statement saying: 'Today's horrendous attack in Nice is an attack against innocent people on a day that celebrates Liberty, Equality, and Fraternity.

'On behalf of all Americans, and especially the great many with close ties to France, I offer our deepest condolences to the friends and family of those who were killed and our hopes for a speedy recovery to those who were injured.

'I was proud to stand alongside French leaders earlier today at Bastille Day celebrations in Paris, and the United States will continue to stand firmly with the French people during this time of tragedy. We will provide whatever support is needed.

'Our embassy in Paris is making every effort to account for the welfare of U.S. citizens in Nice. Any U.S. citizens in Nice should contact friends and family directly to inform them of their well being.'

Hillary Clinton also issued a statement saying that 'we will not allowed ourselves to be intimidated' by attacks that 'seek to undermine our very way of life'.

Meanwhile Donald Trump announced he is postponing a long-anticipated press conference originally scheduled for tomorrow announcing his VP pick, before adding an hour later: 'My prayers and condolences to the victims and families of the terrible tragedy in Nice.'

Identity documents belonging to a 31-year-old French Tunisian were later found in the bullet-riddled truck after the gunman at the wheel was shot dead by police, security sources said.

The shocking attack, the latest to rock France in the recent months, came just hours after President Francois Hollande discusses downgrading the country's state of emergency

The source added: 'The identification of the truck driver is still underway.' The recovered papers indicate the man is a resident of Nice.

The truck driver was said to have shouted 'Allahu Akbar' – God is greatest – before being killed. Pro-ISIS groups have been celebrating the attack but as yet the terror group has not officially claimed responsibility.

A huge cache of guns, grenades and 'larger weapons' were later found inside the lorry, which mounted the pavement at approximately 40mph and steered directly towards hundreds of people watching a fireworks display.

Around 100 revellers are then said to have dived into the sea as panic ensued and holiday crowds desperately ran for their lives.

Anti-terror police swooped in as the city was put on lockdown and residents were warned to stay indoors for their safety.

Addressing the nation, French President Francois Hollande said several children were among the dead, with 80 victims confirmed so far and a further 20 people gravely wounded.