A book club meeting in the Angolan capital of Luanda has landed a group of 17 activists in jail with sentences as long as eight and a half years, including more than five years for prominent hip hop star Lauty Beirão.

A court in the Southern African country issued the verdict on Monday, convicting the group of activists for plotting a rebellion. They were initially arrested and held without charges, but eventually the judiciary settled on counts of preparing acts of rebellion and plotting against the government. These charges reportedly carried maximum sentences of up to 12 years.

After the verdict was announced, the defense said it would appeal the case and asked for suspended sentences until that request plays itself out. In the meantime, however, the court determined the defendants will remain under arrest until the process is over. Domingos da Cruz, a university professor and author, received the longest sentence at eight years and six months. The remaining prisoners got between two and four years.

Since their arrest in June, the group of political activists have become known as the Angola 15, with the addition of two other affiliates who were arrested separately. They were detained on June 20 at a politically-oriented book club meeting, during which the participants were discussing Gene Sharp's From Dictatorship to Democracy — a 20-year-old text about nonviolent political defiance that is often cited in protest movements.

"These boys who were debating their rights are the ones they want to condemn, but President José Eduardo who steals everything is getting protected," Adalia Chivonde, whose son is one of the activists sentenced today, told Reuters following the ruling. "This sentence is garbage for me, it means nothing."

The Angola 15 are part of a growing political movement in the country against the ruling People's Movement for the Liberation of Angola (MPLA) and Angolan President José Eduardo dos Santos, who has been in power for 36 years. Beirão, who goes by the stage name Ikonoklasta, has become known for his activism and criticism.

The youth-propelled dissent began to develop in 2011, particularly after a pro-democracy rally in which Beirão had announced he would take part and perform. Authorities broke up the event within minutes, but the rallly still managed to have lasting effects on the push to get dos Santos out of power — particularly in galvanizing support from middle and upper class, young Angolans. Plummeting oil prices have led to a decline in public services, from sanitation to medical care, while also contributing to a spiraling economy in Africa's second-largest oil exporting nation. The country is currently experiencing its worst yellow fever outbreak in 30 years, largely as a result of sanitation service cuts and trash piling up in the streets. At least 178 have died so far, according to the World Health Organization.

Despite the accusations that the defendants were plotting to overthrow the government, Beirão has maintained that he was arrested because of his opposition to the government and his public criticisms of dos Santos.

The Angola 15 garnered international attention in October when they went on a hunger strike, with Beirão holding out for 36 days. Beirão is a dual Angolan and Portuguese citizen, and his case also sparked protests in Portugal — the colonial power that controlled Angola until 1975. The MPLA rose to power after independence, although a civil war broke out that year and lasted until 2002.

Despite calls from groups like Amnesty International to release the political prisoners, the Angolan government proceeded with the trial, which kicked off in November. Before the trial began, the US Senate's Committee on Foreign Relations signed a letter expressing concern over eroding rights and freedoms in Angola, specifically addressing the fate of the Angola 15.

"While I respect the sovereign right of the Angolan government to investigate and prosecute legitimate threats," wrote Democratic Senator Ben Cardin, the committee's ranking member, "questions remain about the motivation for the arrests of these young people, who — based on reports that I have seen — appear simply to have been discussing methods of peaceful protest."

Throughout the trial, advocates and experts criticized the court for its lack of fairness. During the first week journalists were shut out of court proceedings. In addition to media, family members and independent observers were also barred from the courtroom. In December, Amnesty International said this was a breach of international human rights law.

"These activists, held for over five months on trumped up charges, have not only been unjustly detained, but have also found themselves before a kangaroo court in which the principles of law and justice are being disregarded," Amnesty's deputy director for Southern Africa Muleya Mwananyanda said at the time.

Dos Santos has maintained a tight grip on power during his tenure, but the 73-year-old recently announced he would leave office in 2018. The next elections for parliament, which picks the president, are slated for 2017. Many remain skeptical that leader would actually make an exit, something he has promised before.