All nine people on board a Ukrainian military helicopter have been killed after it was shot down by pro-Russian rebels in the east of the country.
The Ukrainian military said the helicopter, used for transporting military cargo, was hit by a rocket shortly after it took off outside the rebel-held city of Sloviansk on Wednesday.
Those killed were Ukrainian servicemen.
The incident came a day after the rebels vowed to observe a ceasefire until Friday, in response to a Ukrainian government peace plan.
Russian President Vladimir Putin warned that the week-long truce was not enough saying it should be extended to hold substantive talks between Kiev and the separatists.
In May Russian rebels shot down a Ukrainian military helicopter near Sloviansk, killing 14 servicemen including an army general.
The United Nations said clashes between the separatists and army forces in eastern Ukraine have killed an estimated 423 soldiers and civilians between 15 April and 20 June.
UN Assistant Secretary for human rights, Ivan Simonovic also said the number of displaced people has doubled in the past two weeks with the movement of more than 15,000 within the regions of Donetsk and Luhansk.
