DRUG traffickers, like everyone else, only want money because they want what money can buy. But turning dirty cash from drug sales into clean, usable currency has become harder for Mexican drug gangs as a result of tighter banking regulations at home and in the United States, their main market.

The criminals are responding by piggy-backing on cross-border trade to launder their gains.

On September 10th roughly 1,000 law-enforcement officials raided the Garment District of Los Angeles, seizing at least $65m in cash and arresting nine people. According to court documents, several garment businesses allegedly helped drug traffickers ferry proceeds from sales back into Mexico.