Eritrea and Ethiopia have been named as the most censored African countries in a report compiled by the Committee to Protect Journalists (CPJ).

According to the CPJ release, the list is “based on research into the use of tactics ranging from imprisonment and repressive laws in the harassment of journalists and restrictions on Internet access.”

Eritrea ranked number one while Ethiopia came in fourth in the list of 10 most censored countries in the world. The eight other countries on the list are North Korea, Ethiopia, Azerbaijan, Vietnam, Iran, China, Myanmar, and Cuba.

CPJ says Eritrea’s president Isaias Afewerki “has succeeded in his campaign to crush independent journalism, creating a media climate so oppressive that even reporters for state-run news outlets live in constant fear of arrest.”

The tactics used by Eritrea and North Korea – second on the list – mirror each other to a large extent. These regimes use “a combination of media monopoly, harassment, spying, threats of journalist imprisonment, and restriction of journalists' entry into or movements within their countries” to keep their grip on power.

The last accredited international reporter was kicked out of Eritrea in 2007, while those invited occasionally to just interview the president are closely monitored by state security.

“Imprisonment is the most effective form of intimidation and harassment used against journalists,” CPJ adds.

The country is Africa's worst jailer of journalists, and with at least 23 behind bars it ranks third in the world just after Iran, which has jailed 30, and China 44.

Additionally, President Afewerki’s government has deliberately limited internet access through slow dial up connections such that less than one per cent of the population goes online.

Eritrea also has the lowest figure globally of cell phone users, with just 5.6 per cent of the population owning one, making the country the least connected place on earth.

“Fearing the spread of the Arab Spring in 2011, the government scrapped plans to provide mobile Internet for its citizens,” the CPJ report says.

This limited the possibility of accessing information to the point where most Eritreans had no idea that the regimes in countries nearby in Egypt, Tunisia and Libya were being swept out of power.

In Ethiopia, the watchdog says the threat of imprisonment has forced a majority of journalists to seek asylum abroad for fear of persecution.

A crackdown on bloggers and independent publications in 2014 forced over 30 journalists to flee the country, and ahead of the May 2015 elections, authorities have stepped up the campaign to close down the country’s last remaining independent publications through a wave of arrests of journalists and publishers.

“Filing lawsuits against editors and forcing publishers to cease production have left only a handful of independent publications in a country of more than 90 million people,” CPJ says.

Last year, 10 independent bloggers were imprisoned while authorities charged six publications in court for “encouraging terrorism”, forcing at least 16 journalists to flee the country.

Ethiopia has also been accused of using surveillance technology to spy of dissidents at home and abroad.

A report released last year by Citizen Lab, a non-profit research lab that investigates surveillance technology across the world, says Ethiopia has been using a sophisticated malware to spy on Ethiopian journalists based in the US and Western Europe.