The two-year conflict in northern Ethiopia between forces loyal to Prime Minister Abiy Ahmed's government and the Tigray People's Liberation Front, TPLF, killed half a million people, according to the United States, with all parties accused of grave rights abuses.
A peace deal brokered in South Africa by the African Union on November 2 last year brought an end to the fighting in Tigray but clashes have since erupted in other parts of the country, notably in Amhara region, whose forces supported federal troops during the war.
"While the Ethiopian government and its international partners tout the tremendous progress made in the past year, civilians in conflict areas are still bearing the brunt of atrocities," said Laetitia Bader, deputy Africa director at HRW.
The rights group said Eritrean forces, which backed Abiy during the conflict, had "carried out killings, sexual violence, abductions, and pillage, and obstructed humanitarian assistance, and impeded the work of AU monitors" following the signing of the peace deal.
The federal government's decision to impose a six-month state of emergency in early August in Amhara has also raised fears, with the UN-backed Commission of Human Rights Experts on Ethiopia warning of an increase in rights abuses in the region.
HRW spoke to a 24-year-old woman in the North Gondar zone in Amhara who said, "people are getting killed and arrested. Things are much worse. I don't feel safe right now. No one is feeling safe."
Tensions surged in the region after Abiy's government announced in April that it was dismantling regional forces across the country, triggering protests by Amhara nationalists.
Bader said that the country was witnessing "past violators repeat patterns of abuses without consequences."
"Ethiopia's many victims deserve a future that is not marred by recurring abuses and impunity," she added.
It is impossible to verify the situation on the ground in Amhara or Tigray because media access in both regions is heavily restricted.
The International Organization for Migration, IOM, says access to key services including banking, electricity and internet resumed in some parts of Tigray over the past year, but added that one million people remain displaced across the region.