A highly anticipated report on UFOs, prepared by the U.S. intelligence community and delivered to Congress on Friday, does not provide definitive explanations for the U.S. military’s reported encounters with unidentified aerial phenomena, or UAPs.

The report, submitted to Congress and released to the public, encompasses 144 observations of what the government officially refers to as “unidentified aerial phenomenon” dating back to 2004. It was issued by the Office of the Director of National Intelligence in conjunction with a U.S. Navy-led UAP task force.

“In a limited number of incidents, UAP reportedly appeared to exhibit unusual flight characteristics. These observations could be the result of sensor errors, spoofing, or observer misperception and require additional rigorous analysis,” the report said.

The report does not contain the words “alien” or “extraterrestrial” and says further study or “pending scientific advances” may be needed to help explain what are known as UAPs that fall into a vague category that the report lists as “other.”

“Of the 144 reports we are dealing with here, we have no clear indications that there is any non-terrestrial explanation for them — but we will go wherever the data takes us,” a senior U.S. government official told NBC News. “There is a wide, wide range of phenomena that we observe that are ultimately put into the UAP category. There is not one single explanation for UAP, it’s rather a series of things.”

The official added: “We do not have any data that indicates that any of these unidentified air phenomena are part of a foreign collection program nor do we have any data that is indicative of a major technological advancement by a potential adversary.”

The report arrives just weeks after the current NASA chief, Bill Nelson, revealed that he’s directed researchers to “move forward” with looking into “any lines of questioning” about the issue of UFOs/UAPS.