A US citizen has become the first foreign victim of deadly protests that have rocked Oromia, Ethiopia's largest region, in recent months. The US embassy in Ethiopia told news agency AP the American woman died after suffering injuries inflicted by rocks thrown by "unknown individuals" at her vehicle.

Sharon Gray was a postdoctoral researcher at the University of California's plant biology department. She was driving in the outskirts of capital Addis Ababa when the vehicle was attacked.

More on protests in Ethiopia

Fikadu Tessema, head of the Oromia region's spokesman's office, said the agricultural team had not asked for "police protection at the time."

Anti-government protests in Oromia

Demonstrators first took to the streets of Oromia in November 2015 to voice dissent against a government draft plan that aimed to expand the boundaries of the capital Addis Ababa.

They argued the so-called 'Addis Ababa master plan' would lead to forced evictions of Oromo farmers and would undermine the survival of the Oromo culture and language.

The Ethiopian government scrapped the master plan, following increasing agitation that activists claimed led to the death of at least 400 people, a figure the government has rejected.

Protests are continuing, with people calling for self-rule, the liberation of political prisoners and the end of what they perceive as "military regime" in the region.

This includes the cessation of an alleged crackdown by security forces on "peaceful and unarmed" demonstrators, mainly students and farmers.

In October, at least 55 people were killed in a deadly stampede sparked during a protest held at a religious festival in Oromia.

Activists have claimed the stampede was caused after security forces opened fire on protesters. They also claimed the death toll was much higher. However, the government claimed the violence was "instigated by anti-peace forces".