Facebook's mobile ads contributed to significantly increased revenue in the third quarter, even as the company revealed deep losses in its recently acquired WhatsApp business. Facebook said revenue in the three months ended Sept. 30 totaled $3.2 billion, up 59 percent from $2.02 billion in the year-ago period. Mobile ads represented 66 percent of Facebook's advertising revenue.

"This has been a good quarter with strong results," said Mark Zuckerberg, Facebook founder and CEO. "We continue to focus on serving our community well and continue to invest in connecting the world over the next decade."

Facebook also disclosed the financial performance for WhatsApp, a mobile messaging app that the company acquired earlier this month for $22 billion.

According to a filing with the Securities and Exchange Commission on Tuesday, WhatsApp lost $232.5 million in the first six months of 2014, compared to a loss of $58.8 million in the first six months of 2013.

In addition, Facebook said its total number of monthly users reached 1.35 billion in the third quarter, with 864 million users accessing the service every day.

Facebook also warned on a 55 percent to 75 percent increase in spending in 2015 and projected a slowdown in revenue growth this quarter.

The social network is preparing for a spike in expenses next year, when it intends to invest in Whatsapp, Oculus and other products that have yet to show a profit.