Members of the Trilateral Contact Group and the DPR took part in a video conference on 25 September 2014. According to a statement released by the OSCE on the day after the conference, all parties agreed that the fighting had "subsided in recent days", and that the "situation along 70%" of the buffer zone was "calm". They also said that they would "spare no efforts" to strengthen the ceasefire. Scattered violations of the ceasefire continued, nonetheless. In the most significant incident since the start of the ceasefire, seven Ukrainian soldiers died on 29 September when a tank shell struck the armoured personnel carrier that they were travelling in near Donetsk International Airport. A skirmish ensued, leaving many soldiers wounded. Over the next few days, fighting continued around Donetsk International Airport, whilst Donetsk city itself came under heavy shelling. Amidst this renewed violence, OSCE chairman Didier Burkhalter issued a statement that "urged all sides to immediately stop fighting", and also said that putting the ceasefire at risk of collapse would be "irresponsible and deplorable".