The U.S. military has reportedly established a “stealth” shipping corridor in the Strait of Hormuz, a critical oil transport route.

The operation has been in progress for several weeks. Each night, 15-20 tankers traverse the strait via a southern channel along Oman’s coast, transporting approximately 10 million barrels of oil daily, which is about half the pre-war volume, into the global energy market, Axios reported on Wednesday.

A recent two-week U.S. CENTCOM campaign weakened Iran’s radar and maritime surveillance, significantly reducing its ability to monitor traffic in the Strait’s southern channel, as per the report.

But the U.S. military’s role isn’t limited to escorting outbound tankers. They are also aiding empty tankers to enter the Gulf from the Arabian Sea, load oil from regional countries, and then exit, the report said.

The task force at Fort Bragg, North Carolina, coordinates with Gulf partners and tracks daily ship movements through the Strait of Hormuz and into the Arabian Sea, it added.