Federal Bureau of Investigation | Associated Press

The FBI has made a rare foray into media criticism after numerous outlets erroneously reported an arrest in the Boston Marathon bombings:

Contrary to widespread reporting, no arrest has been made in connection with the Boston Marathon attack. Over the past day and a half, there have been a number of press reports based on information from unofficial sources that has been inaccurate. Since these stories often have unintended consequences, we ask the media, particularly at this early stage of the investigation, to exercise caution and attempt to verify information through appropriate official channels before reporting.

Yowch. For its part, the Associated Press explains why it went with the story: A "law enforcement official briefed on the investigation" who "told the Associated Press and other news outlets on Wednesday a suspect was in custody."

The official who spoke to The Associated Press did so on condition of anonymity and stood by the information even after it was disputed.

The official was not authorized to divulge details of the investigation. The official had said the suspect was expected in federal court in Boston.

Here's a Storify that looks at how the conflicting reports have played out.