Jan 6 (Reuters) - Six herders in China who tried to defend grazing land from expropriation by a forestry firm have been sentenced in the resource-rich Inner Mongolia region, a lawyer and family members said on Monday, in a case that has sparked protests.

The unrest in Inner Mongolia is the latest flare up of ethnic tension in China after deadly protests by Muslim Uighur people in the far western Xinjiang region and unrest among Tibetans in the west.

Ethnic Mongols have long complained that their traditional grazing lands have been ruined by mining and desertification, and that the government has tried to force them to settle in permanent dwellings.

The six Mongol herders were sentenced to prison terms ranging from one to two years on Dec. 31 on a charge of "sabotaging production management" by a court in Ongniud Banner, the area of Inner Mongolia where the incident occurred, a lawyer representing one of the accused and family members of two of them told Reuters by telephone.

"The verdict is clearly unjust, this is a land dispute and not a criminal case," said the lawyer, who declined to be identified for fear of government retribution.

"The fact that it's been turned into a criminal case is because of the interference of the local government."

"The villagers have been going to the municipal government and Beijing to petition, and the local government has been criticised for it. They are under great pressure so they had to resort to this approach."

Officials at the court could not be reached.

The herders were arrested in June after a clash with workers from the state-owned Wengniuteqi Shuanghe Forestry, the herders' family members said previously. The herders had accused the workers of illegally occupying grazing land.

Reuters was unable to find contact information for the forestry company.

PROTESTS

The lawyer and family members said the herders had urged officials to address their land problem for years.

"I'm dissatisfied with the verdict," said Sarangowaa, the wife of one of the accused called Tulguur. "My feeling is that they aren't guilty."

Sobdoo, the sister of one of the accused called Tugusbayar, said the herders' plight sparked a protest on Dec. 30 by more than 100 herders outside a government building.

Many Mongols in China go by only one name.

Nearly 200 herders staged protests in front of government buildings of Ongniud Banner and Ulaanhad Municipality on Dec. 30 and 31, said the New York-based Southern Mongolian Human Rights Information Center.

Inner Mongolia, an autonomous region which covers more than a 10th of China's land mass and has its largest coal reserves, was rocked by protests in 2011 after an ethnic Mongol herder was killed by a truck after taking part in protests against pollution caused by a coal mine.

Ethnic Mongols now make up less than 20 percent of the region's population of about 24 million. Before the Communist revolution in 1949, Mongols far outnumbered majority Han Chinese.

The United States has expressed concern about the fate of China's most famous Mongol dissident, Hada, who was sent back to detention almost as soon as he completed a 15-year sentence for separatism in 2010. (Additional reporting by Huang Yan; Editing by Robert Birsel)