HOUSTON, United States

The National Transportation Safety Board (NTSB) sanctioned Boeing on Thursday for its handling of an investigation into a Jan. 5 Alaska Airlines plug blowout, according to media outlets.

Federal officials said the company "blatantly violated NTSB investigative regulations" by "providing non-public investigative information to the media and speculating about possible causes of the Jan. 5 door-plug blowout on a Boeing passenger jet in Portland, Oregon."

The agency accused Senior Vice President of Quality for Boeing commercial airplanes, Elizabeth Lund, of providing the information during a news conference Tuesday in the state of Washington.

The company responded to the sanction in a statement to FOX Business News.

"We deeply regret that some of our comments, intended to make clear our responsibility in the accident and explain the actions we are taking, overstepped the NTSB’s role as the source of investigative information," it said. "We apologize to the NTSB and stand ready to answer any questions as the agency continues its investigation."

Lund said during the news conference at a Boeing factory that the fuselage arrived with "five non-conforming rivets" from its supplier and the mid-exit door plug needed to be opened to get access to the rivets for replacement.

"That plug was opened without the correct paperwork," said Lund, adding that a "lack of compliance to our processes by the correct documentation, using the correct documentation," contributed to what could have been a deadly situation.

As part of the sanction, the NTSB said Boeing would no longer see unpublished information produced during its probe into the incident, which the NTSB previously said involved the midair blowout of the door plug with four missing bolts.

The NTSB said Boeing would, however, keep its status as a party to the investigation into the Alaska Airlines emergency.

"Few entities know the rules better than Boeing," it said.

The agency is subpoenaing the company to appear in an investigative hearing into the case scheduled for Aug. 6 - 7 in Washington, DC.

"Unlike the other parties in the hearing, Boeing will not be allowed to ask questions of other participants," said NTSB officials.