The US government subpoenaed Huawei to turn over information relating to the export, or re-export, of US technology to Cuba, Iran, North Korea, Sudan and Syria, according to The New York Times.

The subpoena from the US Commerce Department is in regard to shipments to those countries over the past five years, and is part of a wider investigation into whether the Chinese firm’s US unit broke export regulations.

The US government is looking for evidence not just of direct sales to the five countries, but also transactions made indirectly through front or shell companies.

Earlier this year, the same government department found rival Chinese vendor ZTE had broken export restrictions. In the wake of the disclosure, three of ZTE’s most senior directors left the company.

Exports of technology to the five countries from the US are limited for a variety of reasons, including the risk of products being used for human rights abuses or breaking US sanctions.

So far, Huawei has not been accused of breaking any regulations, it’s just under investigation. And the subpoena is an administrative one, meaning it does not indicate a criminal inquiry. The company said in a statement it was committed to abiding by laws and regulations wherever it operated.

If the Chinese vendor is found guilty then it could limit its access to US-made components and other technology.

The Chinese network giant has not had the smoothest ride in the US, where it has been the subject of long running national security concerns, expressed by politicians and various government agencies. It is effectively blocked from selling network equipment to leading operators.