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Sept 8 (Reuters) - Australian shares ended lower on Friday with financials being the biggest drag after the banking regulator spelled out plans for a major investigation into back-to-back scandals at Commonwealth Bank of Australia CBA.AX .
The S&P/ASX 200 index .AXJO fell 0.3 percent, or 17.28 points, to 5,672.60. For the week, it fell 0.9 percent.
The Australian Prudential (LON:PRU) Regulation Authority said on Friday it would dig deeper to look into whether CBA's corporate structure had enabled a series of scandals that have hurt the reputation of the nation's biggest bank by market value. "Big Four" banks - Westpac WBC.AX , Commonwealth Bank, National Australia Bank NAB.AX and Australia and New Zealand Banking Group - all ended lower.
The financial index .AXFJ fell 0.8 percent to its lowest close in nearly nine months. It shed 2.6 percent this week, the biggest since May.
Material and energy stocks also lost ground with miner Fortescue Metals Group FMG.AX falling 2.2 percent and Woodside Petroleum WPL.AX declining 0.9 percent.
However, the gold index .AXGD finished up 0.8 percent after prices of the yellow metal hit a fresh one-year high in early trade, despite concerns over a higher royalty payment. GOL/
Gold miners in the state of Western Australia are being hit with an increase in royalty payments under measures released on Thursday to help repair the state's finances following the mining boom collapse. miner Northern Star Resources NST.AX rose 0.7 percent to its highest close since July 14.
The gold index finished the week 2 percent higher.
New Zealand's benchmark S&P/NZX 50 index .NZ50 rose 0.6 percent to 7,851.53, supported by industrial and consumer stocks.
The benchmark index finished the week 0.4 percent higher.
Auckland International Airport AIA.NZ and a2 Milk Company ATM.NZ were the best performers, rising 2.6 percent and 1.9 percent respectively.
Z Energy ZEL.NZ was the biggest drag with a drop of 0.5 percent.