<h1>Undeclared high-speed diesel concealed in cargo barge water tank seized; vessel master and owner's son arrested, probe ongoing</h1> Customs seized over 180 tonnes of undeclared high-speed diesel from a cargo barge and arrested the vessel's master and an owner's son, effecting detention of the contraband and custodial retention of suspects for investigation and prosecution for evasion of customs duty. Investigation disclosed diesel concealed in a water tank not part of the vessel's approved design by the Indian Register of Shipping, effecting evidentiary grounds for regulatory noncompliance and potential safety/design violations and supporting further enforcement action against the vessel owner and related persons. Intelligence indicates possible broader nexus and additional arrests.