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TORONTO, May 28 (Reuters) - Canada's main stock index fell to a more than two-week low on Monday as weaker oil prices pressured energy shares, while materials and financials also lost ground.
* The Toronto Stock Exchange's S&P/TSX composite index ended down 59.53 points, or 0.37 percent, at 16,016.14, its lowest close since May 11.
* The decline for the index came as U.S. markets were closed for Memorial Day and as looming early elections in Italy weighed on European stocks.
* The TSX's energy group retreated 0.8 percent, with major oil producer Suncor Energy Inc down 1.2 percent at C$50.17.
* U.S. crude prices were down 2.1 percent at $66.47 a barrel as Saudi Arabia and Russia said they may increase supplies while U.S. production gains show no sign of slowing.
* Bank of Montreal and Canadian Imperial Bank of Commerce said that cyber attackers may have stolen the data of nearly 90,000 customers in what appeared to be the first significant assault on financial institutions in the country.
* Shares of both banks ended little changed but the overall financials group declined 0.2 percent.
* Nine of the index's 10 main groups ended lower.
* The materials group, which includes precious and base metals miners and fertilizer companies, lost 0.9 percent.
* Bombardier Inc said it had completed the sale of 30 CS300 aircraft to Latvia's Air Baltic Corp, valuing the firm order at about $2.9 billion based on the list price. The company's shares rose 4.4 percent to C$4.56.
* Shares of WestJet Airlines rose 2.5 percent to C$20.88. Pilots who fly for the company's budget carrier Swoop will now be unionized, a concession which resolves a key obstacle in a labor dispute with the airline, a negotiator with the Air Line Pilots Association said. (Reporting by Fergal Smith Editing by James Dalgleish and Tom Brown)