Was the U.S. set up by an Afghan drug lord?

Der Spiegel is reporting that a raid by U.S. Delta Force commandos in Northern Afghanistan this month was set up by an Afghan drug clan to eliminate a rival:

The Americans stormed a guesthouse belonging to the local mayor, who had previously been friendly towards German forces, killing his driver, cook and bodyguard, as well as two of his guests. The US commandos also seized four people. According to the US military, one of those captured was the "target" of the operation, a "high-ranking" member of the terrorist organization al-Qaida.

However, sources in the intelligence community have told SPIEGEL that the US forces were apparently used by a drug clan to take out one of its rivals, who was reportedly one of the men who was killed or detained. The tip-off regarding the location of the al-Qaida terrorist had come from a source close to a member of the Afghan government in Kabul who is reputed to be deeply involved with the illegal drugs trade in Afghanistan.

The German forces who operate in the area are now furious that they're being blamed for the incident. 

With a NATO summit being held later this week, Chancellor Angela Merkel says Germany will step up its training of Afghan police but ruled out committing more troops.

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