TORONTO, Aug. 5 -- Canada's main stock market extended losses on Tuesday as investors were concerned about a slowdown in China's economic growth and renewed geopolitical tensions in Ukraine.

Toronto Stock Exchange's benchmark Standard & Poor/TSX Composite Index was down 27.55 points, or 0.18 percent to 15,187. 71 points. The stock market closed on Monday for a public holiday.

The market sentiment was damped by weak economic data out of China as data company Markit said the HSBC/Markit services PMI fell in July to its lowest since November 2005. The data aroused fear that a slowdown in the world's second-biggest economy may reduce consumption of resources products, one of the heavily weighted sector in S&P/TSX Composite Index.

Also dragging on the market was a report that a Polish official warned about the potential for Russia to invade Ukraine.

The mining sector lost 0.89 percent while the energy sector slipped 0.68 percent. The basic metals producer Lundin Mining Corp. declined 1.56 percent to 6.32 Canadian dollars per share, and the gas and oil giant Encana Corp. edged down 0.61 percent to 22.92 Canadian dollars.

The mining shares were also down amid a large pond holding waste matter. Imperial Metals Corp.' shares dived 40.60 percent to 9.98 Canadian dollars per share although the Vancouver-based miner announced Tuesday that the tailings dam breach that caused a water and tailings discharge at Mount Polley mine early Monday has stabilized.

The health care plunged 2.9 percent. It leading company Valeant Pharmaceuticals International shrank 6.02 percent to 121.44 Canadian dollars apiece as the Canadian drug maker embroiled in a lawsuit to take over Botox-maker Allergan Inc.

However, the industrial sector grew 0.66 percent with Canadian Pacific Railway Ltd. jumping 1.98 percent to 208.68 Canadian dollars per share. And the utilities sector was up 0.62 percent when the gas and electricity services provider surged 3.71 percent to 41.90 Canadian dollars.

On the currency front, the Canadian dollar tumbled to a three- month low Tuesday at 0.9124 U.S. dollar from 0.9152 U.S. dollar on Friday, as the Conference Board of Canada forecast the country's GDP growth in 2014 at only 2 percent. The think tank also believed that Canada's business sector is holding back on investment and that governments are in a restraint mode, leading to a "humdrum" outlook for the Canadian economy.