South Korean consumer electronics giant LG Electronics Inc. said Thursday its third-quarter earnings declined 34 percent from a year earlier largely due to increased marketing costs and growing competition.

Net profit reached 109 billion won ($103 million) in the July-September period, compared with a profit of 165 billion won a year earlier, LG Electronics said in a regulatory filing.

Revenue jumped 4.6 percent on-year to 13.9 trillion won over the cited period, and operating profit surged 27 percent to 217 billion won, it said.

From the previous quarter, however, LG Electronics saw its third-quarter operating income sink 54.6 percent.

LG Electronics said its mobile business suffered a loss due to increased marketing costs and an overall decline in prices of its key products.

Its mobile communications business logged an operating loss of 79.7 billion won in the third quarter, compared with an operating income of 61.2 billion won and 134 billion won, respectively, in the first and second quarters of the year.

LG, a latecomer to the smartphone sector compared with bigger rivals Samsung Electronics Co. and Apple Inc., has been struggling to reclaim its mobile foothold. The company's mobile communications unit, which covers handset sales, had been in the red for the past few years due to increased marketing costs and growing competition from low-end handset makers. (Yonhap news)