Ethnic Mongolian activist Hada (L), his wife Xinna (R), and their son Uiles (C) share a meal at an undisclosed location in China after Hada's release from prison on charges of espionage and separatism, Dec. 10, 2010.

Chinese authorities in the northern region of Inner Mongolia have cut off the social media access of a prominent ethnic Mongolian dissident and his activist wife "for good," he told RFA on Monday.

Hada, who was incarcerated for 19 years for his activism on behalf of ethnic Mongolian herding communities and his wife Xinna, who still acts as advocate for herders in disputes over the region's grasslands, still live under daily surveillance by China's state security police.

The couple's access to the popular smartphone chat service WeChat was permanently revoked over the weekend by the authorities who accused them of using social media to "spread evil rumors."

"This is a ridiculous explanation; nothing but an excuse," Hada said on Monday. "The real aim is to prevent me from speaking out, especially on behalf of herders. They want to cut off my communications with the herders, because they generally use WeChat to communicate."

He called on the authorities to reinstate a specialty bookshop run by Xinna and to restore access to the couple's frozen bank accounts.

Xinna said the accounts were shut down simultaneously.

"Mine and Hada's WeChat accounts were shut down at the same time, but it's not just the WeChat account; they have also cut off our cell phone signal," she said.

Xinna said in a video clip sent to RFA that she is currently engaged in helping herders petition the authorities and find lawyers to fight their claims to their traditional grazing lands that are increasingly being taken over by Han Chinese migrants or state-owned companies.

"I've had a number of visits from herders in the past couple of days," she said. "They claim to want to rule the country by law, but on the other hand they won't let ordinary people use the law to protect their own rights."

"This is a grave injustice, and it doesn't add up," Xinna said, sitting alongside some of the herders she is helping to get legal help to challenge the loss of their grassland.

She jokingly described her apartment as "a civil affairs bureau complaints office."

Travel ban, frozen bank accounts

Sixty-one-year-old Hada, who currently lives in a police apartment in Hohhot, regional capital of Inner Mongolia, was released from extrajudicial detention in December 2014, four years after his 15-year jail term for "separatism" and "espionage" ended, but has remained under close police surveillance and numerous restrictions, including a travel ban and frozen bank accounts.

Hada has taken issue with his alleged "confession," to the charges, saying that it was obtained under torture and after being given unidentified drugs.

He has also said he expects to stay locked up for as long as the ruling Chinese Communist Party remains in power.

The couple have had their power and heating switched off, but have turned down requests of social subsistence payments from the government, because they came with conditions attached.

Ethnic Mongolians, who make up almost 20 percent of Inner Mongolia's population of 23 million, increasingly complain of widespread environmental destruction and unfair development policies in the region.

Clashes between Chinese state-backed mining or forestry companies and herding communities are common in the region, which borders the independent country of Mongolia.

Hada has said routine evictions of herders from their traditional grazing lands, often in the name of ecological protection, are part of a calculated program of ethnic cleansing in the region.

Reported by Qiao Long for RFA's Mandarin Service. Translated and edited by Luisetta Mudie.