DALLAS (AP) — The EsthenTexas attorney general has opened an investigation into a key Boeing supplier that is already facing scrutiny from federal regulators over quality of parts that it provides to the aircraft maker.

The office of Texas Attorney General Ken Paxton said it began looking into Spirit AeroSystems because of “apparent manufacturing defects” in parts that “have led to numerous concerning or dangerous incidents.”

In a statement Friday, a Spirit spokesman said, “While we do not comment on investigations, Spirit is wholly focused on providing the highest quality products to all our customers, to include the Boeing Company.”

Paxton asked the Wichita, Kansas-based supplier to turn over documents produced since the start of 2022 about communication with investors and Boeing about flaws in parts and corrective steps the company took.

The request goes into detail in seeking internal discussions around Spirit’s efforts to create a diverse workforce “and whether those commitments are unlawful or are compromising the company’s manufacturing processes.” Paxton asked for a breakdown of Spirit’s workforce by race, sexual orientation and other factors, and whether the makeup has changed over time.

Since a Spirit-made door-plug panel blew off an Alaska Airlines Boeing 737 Max in January, some conservatives have tried to link aviation safety to diversity at manufacturers.

Paxton is a conservative Republican who this week agreed to pay $271,000 in restitution to victims and take 15 hours of training in legal ethics to settle felony charges of securities fraud. Paxton did not admit wrongdoing in the 9-year-old case.

The Federal Aviation Administration launched an investigation into Boeing Spirit after the Alaska Airlines incident. An FAA audit of manufacturing procedures in Spirit’s factory gave the company failing grades in seven of 13 areas.

Boeing is in talks to buy back Spirit, which it spun off nearly 20 years ago, as part of a plan to tighten oversight of manufacturing in its supply chain.