Washington (CNN) -- A new incident inflaming tensions between the United States and Afghanistan -- this time the alleged massacre of 16 Afghan civilians by a U.S. soldier -- calls into question the chances for stability as the U.S.-led military mission shifts security responsibility to Afghan forces in coming months. Sunday's shootings in Kandahar province followed a series of events that already had sparked anger and distrust between the Afghan and U.S. governments, including the burning of Qurans by U.S. soldiers that led to a violent backlash, including attacks that killed U.S. service members. Now the concern is that an atrocity apparently carried out by a lone American soldier will heighten anti-U.S. sentiments among a civilian population that is key to a successful counterinsurgency strategy against the Taliban.
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Another atrocity heightens anti-U.S. sentiments in Afghanistan
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U.S. officials say the latest shooting won't change the Afghanistan mission or timetable
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Security responsibilities are to be turned over to Afghan forces by the end of 2014
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Last week, two dozen U.S. senators called for speeding up the transition
"If it becomes clear in multiple regions that they would prefer a smaller @placeholder role, especially one not in the lead, I do think that means transitioning to an Afghan lead faster," Jones said.