The New York Times reported that regulators are concerned about new safety risks with the Boeing 737 MAX.

The Times reported that Boeing and regulators have discovered “potential design flaws” with the commercial aircraft.

Initially, the investigation was limited to a software issue, but now problems with wiring related to controlling the tail of the 737 MAX have been discovered, according to the report.

Boeing may need to investigate whether this wiring flaw is also present in its 737 NG model, according to the Times.