The movement of oil across the US has now been disrupted for three days as ransomware closed a pipeline that supplies about 45% of the fuel to the eastern parts of the country.

Colonial Pipeline was forced to close about 5 500 miles of pipeline when if got hit with a ransomware attack.

It is believed the attack is not a nation-state event, but was carried out by a private hacking organisation.

Several sources suggest the ransomware attack was caused by a cyber-criminal gang called DarkSide, which infiltrated Colonial’s network on Thursday and took almost 100Gb of data hostage.

After seizing the data, the hackers locked the data on some computers and servers, before demanding a ransom on Friday.

“On 7 May, the Colonial Pipeline Company learned it was the victim of a cybersecurity attack,” reads the company’s statement. “We have since determined that this incident involves ransomware.

“In response, we proactively took certain systems offline to contain the threat, which has temporarily halted all pipeline operations, and affected some of our IT systems.

“Upon learning of the issue, a leading, third-party cybersecurity firm was engaged, and they have launched an investigation into the nature and scope of this incident, which is ongoing. We have contacted law enforcement and other federal agencies.

“Colonial Pipeline is taking steps to understand and resolve this issue. At this time, our primary focus is the safe and efficient restoration of our service and our efforts to return to normal operation. This process is already underway, and we are working diligently to address this matter and to minimise disruption to our customers and those who rely on Colonial Pipeline.”

As of yesterday evening, the company says it had developed a restart plan, but couldn’t say when the service would be restored.

Colonial’s pipeline transports 2,5-million barrels of gasoline, diesel fuel and jet fuel each day, and this has now been backing up in Texas.

The US government has been forced to issue emergency legislation that relaxes the rules on fuel being delivered by road.

As of today, it’s expected that fuel prices will start to rise in response to the incident.