ROSTOV-ON-DON, Russia (AP) – Hundreds of protesters ransacked and occupied the regional administration building in a southern Russian province Tuesday, demanding the resignation of the region’s president, whose former son-in-law has been linked to a multiple slaying.

Hundreds of armed riot police were standing guard outside the office of regional President Mustafa Batdyev, a duty officer for the Karachayevo-Cherkessiya regional interior ministry said.

The protesters got into the building by battering down the doors with metal barriers. Television footage showed men and women inside breaking windows, pulling down curtains and window frames and throwing papers and potted plants out the windows as uniformed police fled.

Thirty people were injured in the melee, including six law-enforcement officers who were hospitalized, one in serious condition, said the duty officer, who declined to give his name. One woman was seen wielding a police truncheon against an interior ministry soldier.

Nearly 1,000 people, most elderly women, were occupying the building late Tuesday, the duty officer said.

NTV television said Batdyev fled through a back door. But regional police said no officials were in the building at the time of the protest.

The building’s seizure followed weeks of protests over the disappearance of seven shareholders in a chemical company. The men’s charred remains were discovered in a common grave Monday, and prosecutors believe they were killed on Oct. 10 when they were summoned to a meeting at a cottage belonging to Ali Kaitov, Batdyev’s former son-in-law.

Kaitov has been detained on abduction and murder charges. He says he is innocent.

Batdyev has sought to distance himself from Kaitov and had his daughter divorce him as the crisis unfolded. But the provincial leader refused to step down.

The Karachayevo-Cherkessiya region has been plagued by frequent contract murders and other violence, some linked to rivalry between local criminal clans and some spilling over from warring Chechnya, to the east.