ATHENS (Reuters) - Canadian investment fund Fairfax Holdings (>> Fairfax Financial Holdings Ltd) has become the third-biggest shareholder of Greek industrial group Mytilineos (>> Mytilineos Holdings S.A.), acquiring a 5 percent stake worth about 30 million euros ($41 million), the two companies said on Monday.

That is the second Greek investment this year by Fairfax, which is controlled by investor Prem Watsa - known as the "Warren Buffett of Canada".

The deal confirms a trend of overseas funds placing small investments in the bailed-out country, betting on a recovery from its deepest postwar economic slump.

"We continue supporting Greece and believe that the country has made great progress in dealing with its serious economic issues," Watsa said in a Mytlineos bourse filing.

A 5 percent stake in Mytilineos is worth about 30 million euros on the Athens stock exchange.

The company runs southeast Europe's biggest aluminum smelter, produces electricity and controls power station building company METKA (>> Metka S.A.), which has expanded abroad in a bid to escape Greece's recession.

Fairfax said last week it would spend about 20 million euros to raise its stake in Greek property developer Eurobank Properties (>> Eurobank Properties REIC S.A.) (>> Eurobank Ergasias SA) to 41 percent from 19 percent.

The Canadian firm also briefly expressed an interest earlier this year in buying a stake in bailed-out National Bank (NBG) (>> National Bank of Greece), Greece's biggest lender.

Since taking over Fairfax in 1985, Watsa has built a reputation as a shrewd investor through moves such as betting against the U.S. housing market in the last decade and reaping huge profits when the market collapsed.

Fairfax invested last year in beleaguered smartphone maker BlackBerry (>> BlackBerry Ltd) and has signed a tentative deal to buy the entire company.

Index compiler MSCI will demote bailed-out Greece to its emerging market benchmark next month, potentially opening its markets up to a pool of investors more at home with risky assets.

?he MSCI move offers investment possibilities, veteran emerging market fund manager Mark Mobius said on Friday.

U.S. investment firm Japonica Partners, which made a surprise offer for up to 4 billion euros of Greek government bonds in June, said earlier this month it was one of the largest owners of the bonds.

U.S. hedge fund Third Point earlier this year bought a stake in Energean Oil & Gas, a small Greek oil producer, for $60 million.

($1 = 0.7302 euros)

(Editing by Mark Potter)

By Harry Papachristou