Update, 4pm on Friday, July 15: The family confirmed to STV News the couple had been found safe and well.

A Scots couple have been reported missing by their family after the Nice terror attacks that left 84 dead.

Ross and Carole Annie Cowan were in the capital of the French Riviera on holiday when celebrating Bastille Day.

Ms Cowan's sister, Amy Stanton, from Helensburgh in Argyll and Bute, said her family have been unable to contact her sister and husband.

She told STV News she last spoke to her 27-year-old sister in a phone call at 9pm UK time on Thursday, one hour before the attack.

Ms Stanton confirmed she has reported her sister, who works as a primary school teacher, and 30-year-old husband, a tree surgeon, missing to the UK Foreign Office.

She posted on Facebook an urgent appeal for anyone with information about where Mr and Mrs Cowan are to get in touch.

The Foreign Office said it could not confirm if there were any Britons involved, while foreign secretary Boris Johnston said earlier on Friday it was believed one UK national had been injured in Nice.

The attack occurred as thousands celebrated Bastille Day at around 11pm local time on Thursday night.

President Francois Hollande said the incident was a "terrorist crime", while the attacker - reported to be 31-year-old French-Tunisian Mohamed Lahouaiej Bouhlel - was shot dead by police at the scene.

Bouhlel drove the lorry hundreds of metres through the busy Promenade des Anglais, leaving at least 84 dead, including several children, and 18 critically injured in hospital.

Kevin O'Hara, originally from Inverness who has lived in Nice for six years, was making his way to work at an Irish bar near the Promenade.

He told STV News: "As I was tying up my bike, people started running to the left of me, in from the Promenade.

"I didn't hear any screaming really but it was unnerving because the running was a lot like what we saw in Paris.

"We got people into the bar and my friend was hearing from friends in Germany what was happening. He said to me it seems there had been gun fire.

Mr O'Hara said those huddled in the bar originally thought the attack was an accident but the true nature of the incident soon filtered through.

He said: "The first thought that is was an accident really. And then, as the news came on, we started to realise it was much more than that.

"The body count started getting higher and higher. Then we had people who really were escaping what was happening.

"What was noticeable was there were lots of young people - I mean early teenagers, people with their parents, kids, babies."

Mr O'Hara added: "They were up against the windows of the bar so we opened the door to let them in. This is when it really dawned on us that it was a terrorist attack.

"One girl from Venezuela said when the lorry passed through it was zig-zagging and it was targeting people.

"She and her friends were pressed up against the railings.

"In front of her she was just seeing people being mowed down - people just being knocked down."

France was still on high alert after the Paris terror attacks last November in which 130 people were killed at sites including the Bataclan Theatre and Stade de France.

After the terror attack, Police Scotland confirmed it was reviewing safety measures as a precaution but said there was no specific threat to Scotland.

Assistant chief constable Steve Johnson, lead officer for organised crime, counter terrorism and safer communities, said: "Following the tragic events in Nice yesterday, Police Scotland has reviewed security and safety arrangements as a precautionary measure.

"This is something we would do as a matter of course after such events and it is not in relation to any specific information or intelligence.

"Police Scotland is committed to ensuring all communities across the country are as safe as they can be and I would ask the public, especially around crowded places and transport hubs, to remain vigilant and alert, but not alarmed. If you suspect something is wrong, then report it to the police.

"I would stress that there is no specific information which suggests Scotland is at risk of attack, however the UK threat level remains at severe and our communities are not immune from the threat of an attack. That's why I would encourage people to go about their business as normal, but remain vigilant."

First Minister Nicola Sturgeon wrote on Twitter: "My thoughts are with all those affected by this senseless attack on Nice. Scotland stands in sadness and solidarity with France."

The French Consulate in Edinburgh lowered its flag after the attacks, while French players at the Homeless World Cup in Glasgow also paid their respects.