Metro officials knew about deteriorating wooden ties in the section of silver line track where July’s derailment occurred as early as 2013, newly-released interviews with track inspectors showed on Thursday.

Track inspector Jovito Azurin told an investigator he first noted fifteen deteriorating wooden ties in the “K05” section of track where the derailment occurred in a report filed in 2013. Neither he nor any of his supervisors ever followed up on the report, or others that would follow it for years, noting the same problem, before the July 2016 derailment.

RELATED: Metro train derailment felt like 'an earthquake'

“And then to have 15 deteriorating ties in 2013. And now we have a derailment in 2016, but nothing ever happened, you never put a restriction, you never took the track out of service. That’s a concern,” a WMATA investigator told Azurin in an August interview.

The transcript of that interview, along with supporting documents and other similar interviews were released along with the NTSB’s final report on the derailment this week. The report blames the ties deterioration for allowing the tracks to slide too wide for a train to remain on them, causing the derailment.

Taken as a whole, the documents paint a picture of a culture where Metro rail track inspectors did not feel empowered to report dangerous track conditions, and were at times fearful of reprisals from supervisors for taking actions that could hurt the system’s efficiency.

The documents also indicate track inspectors may have falsified periodic inspection reports – simply copying old ones instead of conducting time-consuming new measurements.

“So why are we just keep copying them and handing them in, signing them and handing them in?,” investigator Robert Davis asks another track inspector. “I mean, do [supervisors] tell you, or do you just do it?”

“Both,” replies track walker Lawrence Simmons. “Both.”

In the interviews, conducted in August, Davis said at least two people had already lost their jobs over the derailment, and implies more will follow. WUSA9 could not determine on Thursday whether Azurin or Simmons were still employed by the agency.

WMATA General Manager Paul Wiedefeld has said little about the investigation into the derailment, citing an ongoing criminal investigation. He told reporters on Thursday that Metro’s safety culture still needed improving – an issue he said he takes seriously. He said retaliation against whistleblowers, or fear of it, would not be tolerated.

“If I get anything from an employee that raises any issue like that I basically make sure that that is addressed immediately,” Wiedefeld said.

“Metro managers knew of the needed maintenance that caused the derailment and failed to act,” the union representing Metro’s track workers wrote in a statement on Thursday. “Unless the culture of Metro changes so that the front line workers are listened to, Metro will not be able to meet its challenges. This derailment and its investigation is a terrible reminder of that.”

The derailment report could get significant further attention on Friday, when top Metro and NTSB officials testify before a congressional committee on the topic of Metro’s safety record.