Since fatal protests against the conviction of an opposition leader began, hundreds of people have been detained throughout Senegal, an official said on Sunday.

On Thursday, violence broke out in Dakar and a few other places when opposition leader Ousmane Sonko was given a two-year prison term for "corrupting youth".

The death toll rose to 15 on Friday as a result of further protests.

Read more: 9 killed in Senegal violence after opposition leader Sonko sentenced

"About 500 arrests have been made since the beginning of the protests. Some of those arrested belong to political parties, but the majority are without party affiliation," Interior Minister Antoine Diome told reporters in Dakar.

On Saturday and Sunday, he claimed, there was a "decrease in intensity" of the demonstrations.

According to Diome, the protests are being stoked by outside forces, and "it is the country that is under attack."

The Minister mentioned that crucial infrastructural facilities were damaged by the demonstrators, including a water production plant.

Social media sites were shut down by the government under the pretext of preserving law and order in the West African nation.

Read: Senegalese presidential candidate calls for protests over court ruling

In an effort to stop the "dissemination of hateful and subversive messages," the government has banned mobile phone data, according to the Communication Ministry's statement on Sunday.

Amnesty International criticized the Senegalese government for limiting social media sites.

According to local media, there were still noticeable heavy security force deployments across the city, with army personnel patrolling virtually deserted streets.

In 2021, Sonko was accused of raping Adji Sarr, a worker at a beauty parlor in Dakar, and threatening to kill her. She said Sonko had abused her on five occasions between late 2020 and early 2021. She was under 21 back then.

Sonko was sentenced to two years in prison for influencing young people on Thursday, but the court cleared him of the rape accusations instead, banning him from running for President.

He has not yet been detained and is reportedly in his Dakar residence.

In the 2019 election against President Macky Sall, Sonko came in third place; nevertheless, throughout the trial, he claimed that the case against him was politically motivated to bar him from running in 2024.

International, regional bodies call for calm in Senegal

In the same context, UN Secretary-General Antonio Guterres condemned the violence and "urged all those involved to... exercise restraint," a spokesperson said.

The African Union said its commission president, Moussa Faki Mahamat, strongly condemned the violence and urged leaders to avoid acts that "tarnish the face of Senegalese democracy, of which Africa has always been proud."

The Community of West African States (ECOWAS) called on all parties to "defend the country's laudable reputation as a bastion of peace and stability."

The European Union and Senegal's former colonial power France also expressed concern over the violence.

Amnesty International urged authorities to stop "arbitrary arrests" and lift restrictions on access to social networks. Similarly, the NGO Reporters Without Borders also called on authorities to fully restore internet access.