At least 75 people have been killed during weeks of protests in Ethiopia which have seen soldiers and police firing on demonstrators.

At least 75 people have been killed during weeks of protests in Ethiopia which have seen soldiers and police firing on demonstrators, Human Rights Watch said on Saturday.

"Police and military forces have fired on demonstrations, killing at least 75 protesters and wounding many others, according to activists," HRW said in a statement.

Rights groups have repeatedly criticized Ethiopia's use of anti-terrorism legislation to stifle peaceful dissent, with Washington expressing concern and urging Addis Ababa to employ restraint.

There was no immediate response from Ethiopian government, which has previously put the toll at five dead.

Government spokesman Getachew Reda said the "peaceful demonstrations" that began last month had escalated into violence, accusing protesters of "terrorizing the civilians."

The protests began in November when students opposed government proposals to take over territory in several towns in the Oromia region, sparking fears that Addis Ababa was looking to grab land traditionally occupied by the Oromo people, the country's largest ethnic group.

Demonstrations have taken place in the towns of Haramaya, Jarso, Walliso and Robe among others.