For nearly two weeks, the massacre in San Bernardino has been characterized in the press and by government officials as an ISIS—or, at least, ISIS-inspired—attack in which social media figured prominently in the shooters’ radicalization and planning. On Wednesday, FBI Director James Comey raised major doubts about that characterization when he told reporters that that the husband and wife who killed 14 people in San Bernardino hadn’t posted to social media about radical jihad. That significantly altered the public understanding of how the couple plotted their rampage and what might have been done to stop them.

Previously, anonymous federal officials told journalists that Tashfeen Malik, the wife of Syed Farook, had posted allegiance to ISIS via a Facebook page at the time of the attack. And news reports have focused on Malik’s use of social media to express her jihadist views. That Facebook post in particular, which the FBI has never publicly confirmed, became the strongest evidence of a possible link between the attackers and the militant group and it raised questions about whether ISIS had ordered the couple to attack or merely inspired them to carry out what became the worst terrorist attack on U.S. soil since Sept. 11, 2001.

But Comey told reporters during a press conference at the New York Police Department that reports of public social media posts were incorrect, and that the FBI has so far only found that the shooters were communicating via private messages, which law enforcement agencies would have been unable to see without a warrant.

“These communications are private direct messages, not social media messages,” Comey said. The FBI has searched back to late 2013, Comey said, when the couple were in touch electronically but hadn’t yet met in person. Farook was living in California, and Malik was living in Pakistan. The shooters were “showing signs in that communication of their joint commitment to jihad and to martyrdom.”

But, Comey added, “So far in this investigation, we have found no evidence of posting on social media by either of them at that period of time and thereafter reflecting their commitment to jihad or to martyrdom. I’ve seen some reporting on that and that’s a garble. The investigation continues but we have not found that kind of thing.”

An FBI spokesperson later clarified Comey’s remarks to say the director was only speaking about events before the shooting. Comey didn’t specify which reports had misstated the facts of the case.

In an English-language radio broadcast on the Saturday after the attack, ISIS claimed Farook and Malik as “soldiers of the caliphate.” An Arabic version of the same message referred to them as “supporters,” which The New York Times notes is a term “denoting a less direct connection to the terrorist group.” Terror outfits sometimes claim credit for strikes, even if they’re not directly responsible.

All of which makes the question of exactly how the shooters used social media even more critical to the investigation. It not only would help explain how they carried out the attack, but whether there were warning signs that law enforcement, intelligence, and security agencies may have missed.

During the Republican presidential debate in Las Vegas on Tuesday, Sen. Ted Cruz accused the Obama administration of missing obvious warning signs.

“It's not a lack of competence that is preventing the Obama administration from stopping these attacks,” Cruz said. “It is political correctness. We didn't monitor the Facebook posting of the female San Bernardino terrorist because the Obama DHS [Department of Homeland Security] thought it would be inappropriate. She made a public call to jihad, and they didn't target it.”

While Comey didn’t mention Cruz by name, he contradicted the senator’s assertions.

“This is not public posting, this is private messages back and forth, just like any of us emailing a friend or a family member,” Comey said of the couple’s online communications that law enforcement officials have discovered.

Comey declined to say what service the shooters had used. But he described it as an “Internet service provider communication” that is “very common” and provides both “email service and direct messaging.” Comey said that the service is used to transmit “trillions” of messages, indicating that it is ubiquitous and well known to law enforcement.

Comey added that the investigation has also revealed “no indication of direct contact with foreign terrorist organizations” and the couple. “We still have not seen evidence...that they are part of an organized cell of some sort or that there were other parts to this plan.”

While Comey seemed to punch a hole through one of the key points of the case, it wasn’t entirely clear whether he was contradicting other reports that Malik had expressed her jihadist views via social media, even if not in public postings.

On Monday, the Los Angeles Times reported that Malik “sent at least two private messages on Facebook to a small group of Pakistani friends in 2012 and 2014, pledging her support for Islamic jihad and saying she hoped to join the fight one day.” The paper attributed the information to “two top federal law enforcement officials.”

Comey didn’t specify whether the couple may have used social media services, such as Facebook, to send private messages, so the information may still be accurate. Comey also said the evidence he was describing dated back to late 2013.

The New York Times reported last week that Malik had “talked openly on social media about her views on violent jihad” in “old social media posts” postings, according to law enforcement officials, but that the messages were only recently discovered. It’s not clear from the Times story whether such posts might predate any information that Comey was addressing in his remarks, or whether they were made prior to Malik ever meeting her future husband.

But Comey was adamant that even though the couple were communicating with each other about jihad and martyrdom, there was nothing that the FBI could have done to intercept and read their communications. Farook was a U.S. citizen, and law enforcement couldn’t have read his communications without a court order based on some reason to believe he was associating with terrorists.

“To be clear, and I think this is the way we all want it, we don’t intercept the communications of Americans,” Comey said. “This was an American citizen communicating overseas without predication to believe they’re involved in terrorist activity. If we don’t know something about somebody, were not combing through their emails or direct messages.”

Comey said the government doesn’t have round-the-clock surveillance of Americans or all suspected terrorists despite popular conceptions that U.S. surveillance is omnipotent.

“The government’s only intercepting [private messages] with probable cause and a court order, and if we don’t know anything about the person we have no predication to be doing that in the first place.”

UPDATE 4:45 PM: This story has been updated to reflect further comments from the FBI.