Executives with Europe's biggest bank, HSBC, were subjected to a humiliating onslaught from US senators on Tuesday over revelations that staff at its global subsidiaries laundered billions of dollars for drug cartels, terrorists and pariah states. HSBC's subsidiaries transported billions of dollars of cash in armoured vehicles, cleared suspicious travellers' cheques worth billions, and allowed Mexican drug lords buy to planes with money laundered through Cayman Islands accounts. Other subsidiaries moved money from Iran, Syria and other countries on US sanctions lists, and helped a Saudi bank linked to al-Qaida to shift money to the US. The committee had released a damning report on Monday, which detailed a collapse in HSBC's compliance standards. Executives at the bank [were] consistently warned of problems. HSBC's Mexican operations moved $7bn into the bank's US operations, and according to its own staff, much of that money was tied to drug traffickers. Leigh Winchell, assistant director for investigative programs at US immigration & customs enforcement ... said 47,000 people had lost their lives since 2006 as a result of Mexican drug traffickers. The senators highlighted testimony from Leopoldo Barroso, a former HSBC anti money-laundering director, who told company officials in an exit interview that he was concerned about "allegations of 60% to 70% of laundered proceeds in Mexico" going through HSBC's affiliate.