Sept 3 (Reuters) - The following are the top stories in the Wall Street Journal. Reuters has not verified these stories and does not vouch for their accuracy.

- Five Chinese navy ships are currently operating in the Bering Sea off the coast of Alaska, Pentagon officials said Wednesday, marking the first time the U.S. military has seen them in the area. The officials have been tracking the movements in recent days of three Chinese combat ships, a replenishment vessel and an amphibious landing ship after observing them moving toward the Aleutian Islands, which are split between U.S. and Russian control. (http://on.wsj.com/1hUutNv)

- As Apple Inc prepares to introduce its latest iPhones next week, the company's biggest challenge is one of its making: how to top its own success. Apple's iPhone 6 and iPhone 6 Plus reignited sales growth for the smartphone but analysts predict muted growth for its latest models due out next week. (http://on.wsj.com/1VxIX4e)

- The United Auto Workers union is pitching Detroit auto makers on a proposed health-care purchasing cooperative as a way to lower employee costs and potentially raise funds to finance worker salary increases. (http://on.wsj.com/1hAgKdS)

- The group backing Wisconsin Governor Scott Walker hopes focusing on the Palmetto State and Iowa can help the candidate gain traction after he fell out of the top tier of Republican presidential candidates. (http://on.wsj.com/1FkqH4Z)

- Many small businesses aren't racing to update their checkout systems ahead of an Oct. 1 shift that will put merchants on the hook for some fraudulent card charges. That is the date when retailers are expected to begin using new security technology that accepts credit and debit cards with microchips, and for banks to have replaced their magnetic stripe cards with cards that use chip-enabled technology. (http://on.wsj.com/1ijjBsk)

- The giants of Silicon Valley are bulking up in the European Union's de facto capital, hiring lobbyists and jostling for the favor of the Web's most ambitious regulators. (http://on.wsj.com/1LKENBn)

- China's multibillion-dollar ride-hailing market has erupted into a brawl between Uber and Beijing startup Didi Kuaidi. Uber and Didi Kuaidi are fighting to raise funds for expansion while they compete to woo drivers to their private-car-hailing services and navigate China's tough regulatory environment. (http://on.wsj.com/1NZlGpI) (Compiled by Supriya Kurane in Bengaluru)