The Hong Kong government must ensure its massive HK$1.8 billion (US$229.8 million) subsidy for diesel to mitigate record-high oil prices for the transport sector is not exploited by fuel companies through discount manipulations, an industry leader and a lawmaker have cautioned.Their warnings came shortly after authorities announced a two-month, HK$3-per-litre (38 US cents) diesel relief measure on Thursday to cushion the impact on transport companies amid the ongoing Middle East conflict, with...