* FTSEurofirst 300 index down 1.2 percent
* Banks fall; Banco Santander down
* Commods lower; BG Group slips * Investors turn to defensive stocks
By Joanne Frearson
LONDON, Oct 28 (Reuters) - European shares hit a three-week low on Wednesday as earnings news from Banco Santander and BG Group weighed, with banking and energy stocks the biggest fallers.
By 0959 GMT, the pan-European FTSEurofirst 300 index of top shares was down 1.2 percent at 987.58 points after falling to 986.74, its lowest level since Oct 6. The index, which has lost ground in four of the last five sessions, is still up 19 percent so far this year and has jumped 53 percent since reaching a floor in early March.
"Given the huge rise it is not surprising to see a correction," said Howard Wheeldon, strategist at BGC Partners.
Banks took the most points off the index. The eurozone's biggest bank by market value, Santander, fell 3.1 percent after it posted a 2.8 percent fall in net profit.
Irish banks slumped as traders cited worries over "bad bank" rescue timings. Bank of Ireland and Allied Irish Banks fell 16.8 percent and 14.3 percent, respectively.
Barclays, Societe Generale and UniCredit were down 1.9 to 3.1 percent.
Energy shares featured among the worst performers. BG Group was down 1.9 percent after it posted a 44 percent drop in third-quarter net profits to 484 million pounds ($794.6 million) as gas and oil prices plummeted, although its underlying profits beat forecasts. BP, Petroplus and Total lost 0.8 to 4.8 percent as crude slipped 0.5 percent.
MINERS RETREAT
Miners were on the downside as copper retreated 0.9 percent on demand concerns.
Anglo American, Antofagasta, BHP Billiton, Eurasian Natural Resources Corporation, Rio Tinto and Xstrata lost 1.2 to 3.4 percent.
ArcelorMittal, the world's largest steelmaker, fell 2.8 percent. The company forecast core profit in the fourth quarter of $2.0 to $2.4 billion, below analysts' expectations.
Software companies were also lower. Germany's SAP slumped 6.2 percent after it cut its outlook for software sales and related services revenues for the full year after reporting lower than expected quarterly results. "Sales were disappointing on all levels. Regarding the all-important licence sales, there was a clear shortfall of expectations. Add to this the sales outlook cut," said Nicolas Von Stackelberg, analyst at Oppenheim Research.
On the upside, investors turned to defensive stocks for safety. Drugmakers Sanofi Aventis, Novartis and Roche were 0.4 to 0.8 percent higher, while GlaxoSmithKline added 0.3 percent ahead of Q3 results due at 1200 GMT.
Later in the session, investors will eye U.S. Durable Goods figures to be released at 1230 GMT and U.S. New Home Sales data out at 1400 GMT.
Across Europe, the FTSE 100 index, Germany's DAX and France's CAC 40 were all down 1.2 percent.
(Reporting by Joanne Frearson, editing by John Stonestreet)