In a press statement issued Tuesday night, the Security Council said it "condemned in the strongest terms the killing of 11 and injuring 17 civilians, among them women and children, as a result of shelling of a passenger bus in Volnovakha, Donetsk region, on 13 January 2015."
Security Council members stressed the importance of conducting an objective investigation into the incident and bringing the perpetrators of the attack to justice.
The Security Council also underlined "the need for strict observation of the Minsk protocol of 5 September and its implementing memorandum of 19 September."
The southeastern regions of Ukraine have been suffering from a humanitarian crisis brought about by a Kiev-led military operation launched in spring on local independence supporters that refused to recognize the country's new government.
The conflicting sides signed a ceasefire agreement in Minsk on September 5, 2014. During a Contact Group on Ukraine meeting on September 19, Kiev authorities and representatives of the self-proclaimed people's republics of Donetsk and Luhansk signed a memorandum specifying the implementation of the ceasefire.
Despite the agreements, both Kiev and independence supporters have accused each other of violating the truce.