The leader of the Tigray region said his forces fired rockets at neighboring Eritrea as the growing regional conflict in Ethiopia spreads beyond its borders.

Tigray President Debretsion Gebremichael confirmed the shelling of Eritrea, and said in a text message that the Tigray People’s Liberation Front was fighting 16 Eritrean divisions, without offering proof. He also confirmed a missile strike on Saturday targeting the airport in the Eritrean capital, Asmara, calling it a “legitimate target.”

Officials from the TPLF have blamed Eritrea for helping Ethiopia Prime Minister Abiy Ahmed in the conflict with Tigray.

Abiy said on Sunday that the country is able to achieve its military objectives in Tigray “by itself.” His remark appeared to be in reaction to Debretsion’s claim that Eritrea is fighting alongside Ethiopia’s federal forces.

The government said in a statement Sunday that its “resolve to apprehend the criminal elements within TPLF is stronger than ever” and that its forces were making advances and taking over various areas within the region, without offering specifics.

Conflict broke out in Ethiopia on Nov. 4 when the army struck Tigray in retaliation for an alleged assault on a military base that Abiy blamed on the Tigray region’s government.

Relations between Tigray and Abiy’s administration have been strained since he took office in 2018 and began consolidating power, sidelining the TPLF, once the nation’s preeminent power.

The attacks have led to a humanitarian crisis in the region. Even before the latest spate of violence there were 96,000 refugees and 100,000 internally displaced people in Tigray, Catherine Sozi, the UN’s resident and humanitarian coordinator in Ethiopia, told reporters.

Ethiopia’s Deputy Prime Minister, Demeke Mekonnen Hassen, said Friday evening the government would shortly finish its military exercise against the ruling party in the northern Tigray region.

Addressing members of the diplomatic corp and international agencies, Demeke said the military operation, which has killed hundreds and caused more than 11,000 people to flee to Sudan, was going to plan.