The ship, according to sources at the news agency Bloomberg, has the designation Bella 1 and is Panamanian-flagged. The ship was traveling towards Venezuela to load oil, according to sources with insight into the incident.
The boarding comes a day after the oil tanker Centuries was boarded in waters near Venezuela by the US Coast Guard and military. On December 10, the ship Skipper was seized by the US.
US President Donald Trump has intensified an oil embargo against Venezuela and its leader Nicolás Maduro. Washington's unilateral decision is a clear attempt to isolate the Venezuelan regime and its authoritarian leader.
The White House has not commented on the latest reports, and the sources spoke on condition of anonymity because they are not authorized to speak publicly. Saturday's boarding was only confirmed several hours later by US Homeland Security Secretary Kristi Noem.
Venezuela's government revenues rely heavily on oil exports, which are controlled by state-owned Petróleos de Venezuela SA (PDVSA). Previous boardings have been condemned by Venezuela, which calls them "piracy."
