An attack at a police station in Afghanistan's Wardak province that reportedly killed two American soldiers is only the most recent challenge faced by Defense Secretary Chuck Hagel as he visits the country — including accusations that the U.S. is conspiring with the Taliban.

The Associated Press reports that an Afghan police officer took over a mounted machine gun in the back of a pickup truck earlier today, opening fire on U.S. special forces troops and fellow officers. At least two other policemen were reportedly killed and four wounded, although details are sketchy. Conflicting reports suggest that the American casualties were nonmilitary.

In fact, U.S. troops aren't supposed to be in the region. Midnight Saturday marked a deadline set by Hamid Karzai, the country's president, for Americans to leave the province where the attack occurred. According to the AP, that order stemmed from reports that Afghan troops working with U.S. commandoes had been torturing abusing local residents. One such alleged attack came to light over the weekend in Kandahar province. The Times reports:

The 29-year-old engineering student was standing outside his classroom here on Saturday morning when he said two pickup trucks full of armed men pulled up. The men, said to be members of a C.I.A.-backed Afghan strike force, grabbed him, tied his hands behind his back, draped a black hood over his head and drove him to an undisclosed location where, the student says, he was beaten and whipped. …

Mr. Qayum, who lives in a village that the Taliban frequently visit, said he was interrogated for hours at what Mr. Karzai called an American prison. The captors asked if he knew any Taliban commanders. They asked specifically about his neighbor, a farmer, and whether he could bring the man to them.

Karzai referred to this incident during a press conference over this weekend as additional justification for a ban on coalition troops entering the country's schools. But that comment paled next to Karzai's most incendiary remarks: that he suspected the U.S. and Taliban of working together to ensure a continued U.S. presence in the country past the planned 2014 withdrawal. The comments followed a Taliban bomb attack near where Hagel and Karzai had planned a joint press conference. Following the attack, Karzai spoke alone. The BBC reports:

In a nationally televised speech, President Karzai referred to two Taliban attacks on Saturday in Khost and Kabul that left 19 people dead.

He suggested both the US and Taliban were trying to convince Afghans the situation would worsen after 2014.

He said: "Yesterday's bombings in the name of the Taliban were aimed at serving the foreigners and supporting the presence of the foreigners in Afghanistan and keeping them in Afghanistan by intimidating us."

Both the United States and the Taliban denied any collusion, of course. The American commanding officer in the country called the concept "categorically false." The Department of Defense describes a private conversation between Hagel and Karzai, in which Hagel made similar assurances.

“We did discuss those comments,” the secretary said, responding to a reporter’s question about his meeting with Karzai. “I told the president it was not true that the United States was unilaterally working with the Taliban in trying to negotiate anything.”

Any negotiation with the Taliban to build peace and political consensus in Afghanistan must come from the Afghan government, Hagel said.

This morning, early reports of another source of tension between the two countries: U.S. troops opened fire on two Afghan civilians as they approached a military convoy. Both men, later identified by the AP as employees of a company that repairs police vehicles, were killed.

The official Defense statement quoted above summarizes the secretary's trip: "Hagel’s first visit to Afghanistan as secretary has been eventful." Indeed.