Leaders of Ethiopia's northern Tigray region on Saturday claimed rocket attacks on two airports in a nearby region and threatened to strike neighbouring Eritrea, raising fears that the escalating conflict could spread. The attacks – and threats of more to come – fuelled concern that a conflict Ethiopian Prime Minister Abiy Ahmed vowed would be quick and contained could instead snowball and destabilise the broader Horn of Africa region. Mr Abiy, the winner of last year's Nobel Peace Prize, announced last week he had ordered military operations in Tigray, saying the move came in response to attacks on federal military camps by the regional ruling party, the Tigray People's Liberation Front (TPLF). Hundreds of people are reported to have been killed in the conflict so far, some in a gruesome massacre documented by Amnesty International. Thousands have fled fighting and air strikes in Tigray, whose leaders Mr Abiy accuses of seeking to destabilise the country. As of Friday evening, at least 21,000 Ethiopians had fled across the border into Sudan, according to Sudan's refugee agency. The strikes on airports took place on Friday night in two cities of the neighbouring Amhara region, Bahir Dar and Gondar. The federal government acknowledged that "the airport areas have sustained damages", while a doctor in Gondar said two soldiers were killed and up to 15 injured. "Yesterday evening we've inflicted heavy damages on the military components of the Gondar and Bahir Dar airports," Getachew Reda, a senior member of the TPLF, said in a statement on Saturday. He reiterated claims by the TPLF that Eritrean soldiers are involved in the fighting, which Ethiopia denies. And he said the TPLF would not hesitate to strike locations inside Eritrea – Ethiopia's traditional foe – including its capital, Asmara. "Whether they lift from Asmara or Bahir Dar to attack Tigray … will commit retaliatory measures. We will undertake missile attacks on selected targets in addition to the airports," he said. "We will conduct missile attacks to foil military movements in Massawa and Asmara", he added. Mr Abiy on Friday declared the TPLF was in the "throes of death", but the party has vowed to fight on. A communications blackout in the region has made it difficult to assess competing claims about how the fighting is going. The TPLF dominated Ethiopian politics for nearly three decades before Abiy took office in 2018 on the back of several years of anti-government protests. Since then, the TPLF has complained of being sidelined and scapegoated for the country's woes. The feud grew more bitter after Tigray went ahead with its own elections in September – defying a nationwide ban on all polls imposed because of the coronavirus pandemic – and tried to brand Mr Abiy an illegitimate ruler.