Brother of Hassan Benkhedda says Algerian authorities and ‘thugs’ are responsible for his death.

The son of Algeria‘s first prime minister has died while taking part in a protest against President Abdelaziz Bouteflika’s bid for a fifth term in office, a government official and a family member said on Saturday.

Interior Minister Noureddine Bedoui identified the man as Hassan Benkhedda, a son of the late Benyoucef Benkhedda, who took power after the country gained independence from France in 1962.

“The forensic medical investigations will clarify causes and circumstances of his death,” the minister said in a tweet.

Benkhedda, believed to be in his 50s, was killed in a clash between police and “thugs unrelated to the protesters,” the minister said in a separate statement online.

Family members, however, dispute that explanation.

In a Facebook post, Salim Benkhedda said that his brother Hassan had participated in the mass protests near the presidential palace in central Algiers on Friday and blamed what he called the “ruling gang and its thugs” for the death.

The death is the first to happen in protests that erupted more than a week ago against Bouteflika’s plan to run in next month’s presidential election.

Many Algerians believe Bouteflika is unfit to hold the presidency. The 81-year-old suffered a stroke in 2013 and is rarely seen in public.

Nevertheless, his campaign manager said this week that Bouteflika would submit his candidacy documents for the April 18 election on Sunday, the final day for registration.

On Friday, tens of thousands of Algerians took to the streets in several parts of the country against Bouteflika’s re-election plan.

Some 56 policemen were injured during the protests and around 45 protesters were arrested, according to a security agency.

In a statement carried by the Algerian state television, the security general directorate said that seven people were also injured.

Algerian authorities have said they will be making a major announcement concerning the protests on Saturday evening.