A wealthy tech entrepreneur and his family were tied up and robbed at knifepoint after thieves demanded cryptocurrency.

Oliver von Landsberg-Sadie, his wife Sarah, and their two children were allegedly restrained by the group as they demanded the keycode to the businessman's electronic wallet.

The suspects, including an alleged perpetrator police believe to be in his late teens, left without the digital currency but 'trashed' Mr von Landsberg-Sadie's sprawling five-bedroom home in Maidenhead, Berkshire.

They made off with cash, silver and jewellery following the terrifying ordeal on April 2.

The businessman, 47, told the Mail: 'It's the sort of thing you see on the movies and never think will happen to you.

'They were only after crypto.'

The brazen thieves bypassed the Aston Martin on the family's driveway and initially only demanded crypto details.

'They had no interest in the car, for example, because that's traceable,' he said.

'Crypto is of course not the only thing burglars target but it's true that it can be as vulnerable to theft as cash or jewellery if not kept securely.'

He added: 'In my case, to the burglars' disappointment, I securely kept zero crypto.

'We live in a pretty safe country here but I'm from South Africa and nothing like this ever happened to me there.

'People who are in a particular position or who have public-facing profiles have to be more vigilant.

'It's not just about crypto, it's about anything of value.'

He also warned fellow tech entrepreneurs to keep safe. 

In a social media post, he said: 'This is an urgent warning to all my fellow founders, CEOs, people with any public profile at all in the crypto space, there is clearly an organised campaign right now and I ask you to be more vigilant with your personal safety.

'I am ok, my family are ok, my house is trashed but the police are all over it.

'It is my duty to get this message out as quickly as possible, no idea who is next on their list. Be safe.'

In a social media post, fellow tech entrepreneur Didar Bekbauov wrote: 'Glad you and your family are safe.

'This is a serious and growing threat for anyone with public exposure in crypto.

'Physical security is something most founders don't think about until something like this happens. Take care of yourself.'

Thames Valley Police said the thieves broke into the three-storey detached home, valued at around £1.5 million, at around 10pm while the homeowners were in the kitchen.

Some of the suspects wore gloves and a face covering, detectives said.

They were described as a black man in his mid-20s, a black male in his late teens, an Asian man in his late 20s or early 30s, and a black man in his early 30s.

No arrests have been made.

Mr von Landsberg-Sadie said the men were 'only after crypto' and had no interest in the Aston Martin car parked on his driveway.

But they made off without any digital currency because he does not have it, he said.

The South African national is chief executive of Greater Things, a company using AI to help tech start-ups.

He previously founded leading London-based crypto firm the BCB Group.

A cryptocurrency is a decentralised digital currency that can be used for transactions online.

It is the internet's version of money - unique pieces of digital code that can be transferred from one person to another.

Unlike centralised currencies such as the Pound, there is no governmental authority that manages cryptocurrencies or how much they are worth.

Crytocurrencies use what is known as blockchain technology - an open ledger that records transactions in code.

They are particularly popular with criminals seeking to keep assets hidden from authorities.

Iran is currently demanding shipping companies pay enormous tolls in cryptocurrency to access the Strait of Hormuz.