The UN Security Council heard fears of a further escalation in Israeli-Palestinian violence in the Gaza Strip during emergency talks Friday despite a failure to agree a joint statement on clashes that have left at least 16 people dead. UN Secretary-General Antonio Guterres called for an "independent and transparent investigation" and reaffirmed "the readiness" of the world body to revitalize peace efforts, a spokesperson said. "He also appeals to those concerned to refrain from any act that could lead to further casualties and in particular any measures that could place civilians in harms way," UN spokesman Farhan Haq said. Kuwait requested the meeting to discuss the unraveling situation in Gaza, where Palestinians said Israeli fire killed 16 people in the conflicts deadliest single day since the 2014 Gaza war. "There is fear that the situation might deteriorate in the coming days," said assistant UN secretary general for political affairs, Taye-Brook Zerihoun, urging maximum restraint. "Israel must uphold its responsibilities under international human rights and humanitarian law. Lethal force should only be used as a last resort with any resulting fatalities properly investigated by the authorities," Zerihoun said. Britain and the United States expressed regret that the timing of the meeting -- the first night of Passover -- meant Israeli officials could not attend. Leading ambassadors sent deputies in their place. "Its vital that this Council be balanced in its approach," a US diplomat told the meeting. "We should have found an arrangement for all parties to participate tonight," he added. "We are deeply saddened by the loss of life today," the diplomat added. "The risk of escalation is very real," the French representative said. "There is the possibility of a new conflict in the Gaza Strip." In a written statement before the meeting, Israels ambassador to the United Nations, Danny Danon, blamed Hamas for the violence. The violence broke out as tens of thousands of Gazans marched near the Israeli border to demand the right of return for Palestinian refugees who fled or were expelled since the creation of Israel. Israeli troops used tear gas and live fire to force back Palestinians who approached the heavily fortified border fence.  Israeli tank fire and an air strike also targeted three Hamas sites in the Gaza Strip after what the military said was an attempted shooting attack against soldiers along the border that caused no injuries. The health ministry in Gaza said 16 Palestinians were killed by Israeli forces and more than 1,400 were injured, including 758 by live fire, with the remainder hurt by rubber bullets and tear gas.