The government has sought to arrest leaders of the Tigray People's Liberation Front (TPLF), the group that is fighting Ethiopian government forces.
Ethiopian authorities have detained several senior officials from Tigray, including members of the government's last administration in the conflict-ravaged region.
Daniel Bekele, Chief Commissioner of the Ethiopian Human Rights Commission, did not name the officials and declined to comment on the reasons for the arrests.
"We know about the arrests of at least eight," he told Reuters, adding that some of the prisoners had been sent to Tigray's neighbouring region of Afar.
The spokesman for Ethiopian Justice Minister Gedion Timothewos, federal police spokesman Jeylan Abdi and Afar regional spokesman Ahmed Koloyta did not immediately respond to requests for comment.
Any such arrests would be highly unusual.
The government has previously sought to arrest leaders of the Tigray People's Liberation Front (TPLF), the group that is fighting Ethiopian government forces.
But many of those arrested were working on behalf of the government, and they included one member of the ruling party, said a lawyer working with the detainees and a source close to the detainees, both asking not to be named for fear of reprisal.
War erupted between the TPLF and the central government in November 2020. The military took control of most of Tigray within three weeks and the government appointed an interim administration, which many of the arrested officials served in.
But Tigrayan forces forced the military to pull out of Tigray at the end of June 2021 - leaving its capital in the hands of the TPLF. The fighting has now mostly ground to a stalemate.
The lawyer and the source said 12 Tigrayan officials, an activist and another man were arrested in a series of raids on March 7 and 8. They have not yet been charged and the reasons for the arrests are unclear, the lawyer said.
Those detained who served under Ethiopia's federal government include Abera Nigus, the former head of Tigray's justice bureau, the lawyer and the source said.
Others included a member of Abiy's ruling Prosperity Party, an administrator for one of Tigray's six zones and the deputy director of the regional state media, the lawyer and the source added.
The government has repeatedly said it is fighting against the TPLF and not Tigrayans in general. Aid groups say the conflict has displaced millions.
The United Nations has said at least 15,000 Tigrayan civilians were arrested or imprisoned across Ethiopia under a state of emergency declared in November and lifted last month. Police have denied targeting Tigrayans due to their ethnicity.