Iran’s impoverished southeast experienced wide disruptions of internet service over the past week, internet experts said Saturday, as unrest gripped the remote province after a string of fatal border shootings.

Several rights groups reported in a joint statement that authorities shut down the mobile data network in the restive provinces of Sistan and Baluchistan, calling the disruptions an apparent “tool to conceal” the government’s harsh crackdown on protests.

The reports of internet interference come as Iranian authorities and semi-official news agencies increasingly acknowledge the turmoil challenging local authorities in the southeast — a highly sensitive matter in a country that seeks to repress all hints of political dissent. For three days starting Wednesday, the government shut down the mobile data network across Sistan and Baluchistan, where 96 percent of the population accesses the internet only through their phones, rights groups said, crippling the key communication tool. Residents reported a restoration of internet access.

“This is Iran’s traditional response to any kind of protest,” Amir Rashidi from Miaan Group, a human rights organization that focuses on digital security in the Middle East, told The Associated Press on Saturday.

“Shutting down the internet to block news and pictures getting out makes (authorities) feel more comfortable opening fire.” The week saw a series of escalating confrontations between police and protesters. Crowds with light arms and grenade launchers descended on Kurin checkpoint near Iran’s border with Pakistan, Abouzar Mehdi Nakhaie, the governor of Zahedan, said in comments carried by Iran’s semi-official ISNA news agency.