Samsung Electronics has seen its quarterly operating profit fall to its lowest level in more than three years because of slowing smartphone sales.
The South Korean company said profit fell 60% to 4.1tn won ($3.8bn; £2.5bn) in the three months to September.
The results were in line with the firm's preliminary estimates released earlier this month. Shares of the world's biggest smartphone-maker have lost nearly 20% of their value this year.
Samsung's mobile division, its biggest business, has been struggling to maintain its dominance against rivals such as Apple, which recently released the new iPhone 6.
Its flagship Galaxy smartphone line has been losing market share to Chinese smartphone-makers Xiaomi and Lenovo, which sell cheaper models that also have large screens and multiple features.
Samsung said market competition is "expected to further intensify".
"Although the company anticipates a demand growth for the recently launched Galaxy Note 4 and new middle-end smartphone models, uncertainty remains," the firm said in a statement.
It said the year-end surge in competitor smartphone launches "may require a potential increase in marketing expenses associated with year-end promotions".