'For almost a week, Sudan has been completely cut off from the internet. It started slowly, with a series of intermittent disruptions during months of protests against former President Omar al-Bashir's 30-year rule.
Al-Bashir was toppled in April, but the protests did not end and demonstrators began demanding that the Transitional Military Council (TMC) cede power to a civlian-led government.
On June 3, as security forces violently dispersed a protest camp in the capital, Khartoum, all mobile access to the internet was cut.
A week later, after reports of killings, rapes and other abuses began to emerge, landline access was also shut down, severing the flow of information from Sudan to the outside world.
The situation is alarming, but not unique.
As more and more people rely on the internet for everything from communication to banking, authorities around the world are increasingly switching it off.
Here, Al Jazeera explains how and why blackouts happen and the crippling effects they can have.
What is an internet blackout?
A blackout happens when a country's access to the internet is completely cut, preventing people from getting online.
Cyberattacks or damage to the undersea cables that carry telecommunications signals can cause this to happen, but the most common reason is that authorities choose to turn off access.
Deliberate internet blackouts by authorities have been recorded as far back as 2005, but the practice became more widely-known after Egypt's week-long government-imposed blackout during its 2011 uprising.'
Read more: Internet blackouts: The rise of government-imposed shutdowns
