LONDON — HSBC’s legal troubles are growing: The British tax authorities said Friday that they were looking into a list of HSBC clients with bank accounts in the tax haven of Jersey.

Her Majesty’s Revenue and Customs, Britain’s tax authority, is investigating more than 4,000 accounts in Jersey that belong to British clients after receiving details from a whistle-blower. The list includes a drug dealer and a man convicted of possessing more than 300 weapons at his home in the south of England, The Daily Telegraph reported.