Chinese search giant Baidu Inc. reported its first loss since going public in 2005, reflecting slowing sales and rising business costs.

Baidu posted a net loss of 327 million yuan ($47.3 million) for the first quarter ended March 31, compared with net income of 6.69 billion yuan a year earlier, according to Baidu’s unaudited financial report released Thursday.

Revenue grew 15% for the quarter to 24.1 billion yuan, Baidu said. Online marketing revenues, a major contributor to overall sales, rose nearly 3% to 17.66 billion yuan, mainly backed by growth in education, retail and business services, the company said, while health care, online games services and financial services were less vibrant.

"Despite government policies to improve the market condition for small and medium enterprises, we anticipate online marketing in the near term to face a challenging environment," Chief Financial Officer Herman Yu said.

For the second quarter of 2019, Baidu expects revenue to be between 25.1 billion yuan and 26.6 billion yuan, falling below analysts’ expectations. Its shares were down 8% in extended trading.

At the end of March 2019, the company had 174 million daily active users, up 28% from the year-ago period.

While announcing the first quarter results, Baidu said it accepted the resignation of Xiang Hailong, senior vice president of the search business. Xiang served at Baidu for 14 years.