Ukrainian security forces and pro-Russia rebels are fighting for control of Donetsk airport in eastern Ukraine.
Rebel leader Alexander Zakharchenko was quoted by BBC News as saying that the airport is now 95% under separatist control.
However, Ukrainian military spokesman Andriy Lysenko denied the claims and said that it is still controlled by the Ukrainian Government, with reinforcements on the way.
"They have manpower, they have munitions and food supplies. They have everything to sustain defence," Lysenko said.
"Reinforcements are coming regularly because the airport has not been surrounded."
On 1 October, anti-government protesters attacked the airport using tanks, multiple-launch rocket systems, artillery and mortars, and followed it up with small-arms fire the following day.
Ukrainian Government spokesman Vladyslav Seleznyov told Kanal 5 TV that the military repelled four attacks on the airport, destroying a T-64 tank and killing seven rebels.
Over the past several weeks, the separatists have attempted to seize the airport, which has been used by soldiers to shell rebel positions in and around the city.
In a further development, an International Committee of the Red Cross employee was killed by shelling in the centre of Donetsk.
At least ten people, including parents and teachers, were killed when a school and a minibus were struck by shelling in the city.
Meanwhile, the rebels' official website, DNR Today, blamed the Ukrainian artillery for the attack, claiming rebels do not have the relevant weaponry.
The renewed fighting threatens a fragile ceasefire agreed last month, which aimed to establish a 30km buffer zone.
Both sides have since accused each other of violating the ceasefire.
Since April, the conflict has killed more than 3,500 people, injuring several hundred others.
Image: Pro-Russia rebels attacked Donetsk International Airport with tanks, artillery and mortars on 1 October. Photo: courtesy of Michael1238.