Ethiopian Prime Minister Abiy Ahmed has reportedly joined the front line where government forces are battling rebels from the Tigray region, prompting US-led international calls for a diplomatic solution and immediate ceasefire.
The fighting in the north of Africa's second-most populous country has killed thousands of people and forced hundreds of thousands into famine-like conditions over the past year.
Foreign governments have told their citizens to leave amid the escalating war and fears the Tigrayan rebels could march on the capital Addis Ababa.
Mr Abiy, winner of the 2019 Nobel Peace Prize, "is now leading the counter-offensive" and "has been giving leadership from the battlefield as of yesterday," state-affiliated Fana Broadcasting Corporate reported.
It was not clear where Mr Abiy, a former radio operator in the military who rose to lieutenant colonel, had deployed.
State media did not broadcast images of him in the field and officials have not responded to requests for details about his whereabouts.
Addressing reports of Mr Abiy at the front, the US State Department said "there is no military solution" to Ethiopia's civil war.
"We urge all parties to refrain from inflammatory and bellicose rhetoric, to use restraint, respect human rights, allow humanitarian access, and protect civilians."
A day earlier Washington's special envoy for the Horn of Africa, Jeffrey Feltman, said "nascent progress" risked being "outpaced by the military escalation by the two sides".
Other foreign envoys have also been frantically pushing for a ceasefire, although there have been few signs a breakthrough is coming.
On Wednesday, UN Secretary General Antonio Guterres called for a swift end to the fighting while on a visit to Colombia to mark the fifth anniversary of a peace deal between the government and former FARC rebels.
"The peace process in Colombia inspires me to make an urgent appeal today to the protagonists of the conflict in Ethiopia for an unconditional and immediate ceasefire to save the country," he said.
The war erupted in November last year when Mr Abiy sent troops into Tigray to topple its ruling party, the Tigray People's Liberation Front.