HAVANA: Cuba's communist leadership has always viewed the internet with suspicion while trying desperately to control it.

Raul Castro, the former president and leader of the Communist Party, who officially retired on Monday, has blasted the medium for "lies," "manipulation" and "subversion."

But for Cuba's 11.2 million people who have long been amongst the least connected people on the planet, the internet has become a favorite tool of the outlawed opposition.

The arrival of 3G in 2018 was a boon. There are now 4.2 million Cubans using 3G.

President Miguel Diaz-Canel was originally a fan and encouraged the "informatization of society," but he's quickly become disillusioned with the internet, faced with its enthusiastic use to criticize authorities.

On Monday, while 300 delegates met for the Communist Party congress in Havana, an amateur video went viral on social media.

It showed dissident artist Luis Manuel Otero Alcantara being arrested in a poor neighborhood of the capital.

Dozens of activists, independent journalists and artists have complained on Twitter that police are preventing them from leaving their homes -- a favorite ploy by authorities to prevent mass gatherings that could lead to anti-government protests.

Others complained of their internet and telephone lines being shut down.