BENGALURU, INDIA – Facebook has tentatively concluded that spammers looking to make money, and not a nation-state, were behind the largest-ever data theft at the social media company, the Wall Street Journal reported on Wednesday. The people behind the attack were a group of Facebook and Instagram spammers who present themselves as a digital marketing company and whose activities were previously known to Facebook's security team, the Journal reported, citing people familiar with the company's internal investigation. Last week, Facebook said cyberattackers had stolen data from 29 million Facebook accounts using an automated program that moved from one friend to the next, adding that the data theft had hit fewer than the 50 million profiles it initially reported. Facebook said in an email that it was cooperating with the Federal Bureau of Investigation on this matter. The breach has left users more vulnerable to targeted phishing attacks and could deepen unease about posting to a service whose privacy, moderation and security practices have been called into question by a number of scandals, cybersecurity experts and financial analysts have said.