US Internet giant Yahoo is in talks to buy the online video service NDN, which could help it compete with YouTube, The Wall Street Journal reported. Yahoo could pay $300 million in the deal for News Distribution Network, according to unnamed sources cited by the Journal. A Yahoo spokeswoman declined comment. And NDN did not immediately respond to requests for comment. Video is one of the pillars of Yahoo CEO Marissa Mayer's strategy to boost the company's growth. It could be Yahoo's second largest acquisition under Mayer, the report added. Last year, Yahoo bought Tumblr for $1.1 billion.