At least two large oil tankers have entered the Persian Gulf, apparently bound for Iran in defiance of Washington’s blockade on Iranian ports, AFP reports citing tracking data.

Two very large crude carriers (VLCC), the RHN and the Alicia, have been observed near Iran’s coast in the Gulf, having passed the strait after the US imposed its blockade on Monday, according to data from maritime tracking firm Kpler.

The two supertankers had previously broadcast their destinations as Iraq but changed them to “for order” as they passed the strait, Kpler data shows.

A third VLCC, the Agios Fanouris I, and a liquid petroleum gas tanker, the G Summer, were also in the Gulf after crossing the strait during the blockade and reported their destinations as Iraq, the data shows.

Two other vessels, the container ship Zaynar 2 and empty general cargo ship Neshat, have also crossed the strait and have been detected near the Iranian port of Bandar Abbas, according to Kpler’s tracking platform MarineTraffic.