* STOXX 600 ends down 0.2 pct
* Gemalto plummets on profit warning, broker downgrades
* Cartel concerns hit carmakers
* Airlines fall as Ryanair flags fares to fall in summer
* Julius Baer jumps on biggest inflows since fin crisis (Updates with closing prices)
By Helen Reid
LONDON, July 24 (Reuters) - European shares dipped on Monday with automakers hitting their lowest level this year after anti-trust regulators opened an investigation, while price war worries hurt airlines.
The pan-European STOXX 600 fell 0.2 percent as gains in heavyweight financials helped offset losses in other sectors. Euro zone bluechips ended flat.
Gemalto dropped 19.7 percent after the digital security company on Friday warned on profit for the fourth time since October, citing continued weakness in its SIM-card and U.S. payments operations.
"We continue to see both these businesses with double-digit (sales) declines given our view of limited unit growth and pricing pressures," Credit Suisse analysts said as they cut their target price.
Societe Generale and Natixis both reduced their recommendations on the stock following the warning.
Shares in carmakers fell after EU antitrust regulators said they were investigating allegations of a cartel, with Volkswagen , Peugeot, Daimler, Renault and BMW between 1.3 and 2.8 percent lower.
This brought the autos index to a seven-month low and made it the day's worst-performing sector, with a fall of 1.4 percent by the close.
"It's clearly bad for sentiment, which was already burned by the emissions scandal," Michael Punzet, autos analyst at DZ Bank said, adding that he expects "high volatility related to the upcoming newsflow".
Jefferies analysts said: "One cannot rule out material fines should anti-competitive behaviour be confirmed, up to the maximum allowed under EU rules." That would be 10 percent of annual turnover, they added.
Budget airline Ryanair fell 1.1 percent after it warned summer fares would face sharp cuts, though it said profit soared 55 percent in its first quarter.
Wizz Air and EasyJet sank 1.3 and 2.8 percent, while Lufthansa rose 0.5 percent.
Switzerland's third largest private bank Julius Baer rose 4.5 percent after reporting its biggest inflows since the financial crisis for its first half, helped by a push to recruit more private bankers.
"We expect the market EPS (earnings per share) estimates to go up by a mid-single digit figure and argue that Baer deserves higher price-to-earnings multiples reflecting stronger net new assets," Baader Helvea analysts said.
Among leading gainers was B&M European Value Retail , up 4.9 percent after a report that Asda, the British supermarket arm of U.S. retail giant Wal-Mart, was considering a 4.4 billion pound takeover bid.
Shares in Dutch healthcare technology firm Philips also gained 4 percent after its profit rose 15 percent in the second quarter, helped by strong sales of consumer personal care products.
Reporting by Helen Reid and Danilo Masoni; editing by John Stonestreet and Alexander Smith