JUBA, South Sudan — Patients in South Sudan have been shot to death in their hospital beds and medical facilities have been looted and burned to the ground, forcing the aid group Doctors Without Borders to examine its operations here.The extreme violence and lack of respect for health care workers shown by South Sudan's warring sides has made Doctors Without Borders' work almost impossible, the international group said in a statement Wednesday.Members of the aid group discovered at least 14 dead bodies in a hospital in the contested city of Malakal over the weekend, said the statement. Several of the dead bodies had been shot while lying in their beds, the group said. Rebels have been fighting government forces for control of the city, the capital of an oil-producing state.In addition, Doctors Without Borders' facilities in the towns of Leer and Bentiu have been looted and completely destroyed, said the group's leader in South Sudan Raphael Gorgeu. He said Doctors Without Borders does not want to leave South Sudan but must look at the safety of its workers.The men carrying out the fighting have shown "absolutely no respect for health care workers," he said. He asked how the group could "stay to the very last moment with the guarantee that our staff and patients will not be targeted?"Gorgeu said the group does not want to pull out of South Sudan, where 800,000 people are displaced and 3.2 million in immediate need of food due to fighting that broke out in mid-December. Thousands have died in the violence.At the end of January thousands of residents fled as fighting broke out in Leer, the home town of rebel leader and former Vice President Riek Machar. Doctors Without Borders has worked in Leer for 25 years, evacuated staff while 240 others fled into the bush. They returned this week to find their hospital — a facility that served 300,000 people — destroyed."We don't want to leave South Sudan, definitely not, but we have to look at things very carefully now," he said. "It is not the investment we put in but the trust and the respect we put in that is actually put into question."The situation in South Sudan is to be discussed at a hearing by a U.S. House of Representatives committee later Wednesday. Rep. Chris Smith of New Jersey said the hearing would examine the need for a more unified and proactive U.S. policy in the region.John Prendergast, co-founder of the U.S. advocacy group the Enough Project, said a "nightmare" scenario is unfolding in the Sudan-South Sudan region."Given the escalating crisis being faced by the two countries and the threat posed by a regionalization of the wars, a much more robust and proactive approach is needed," he said.