NEW YORK - Shares of US social media giant Facebook tumbled nearly 20 percent on Thursday after its second-quarter revenue and user growth disappointed investors.

The plunge knocked roughly $120 billion in market value off the stock, which would be the largest ever loss of value in one day in US stock market history.

The tech company missed projections on revenue and global daily active users for the second quarter. It said Wednesday after the closing bell that its quarterly revenue reached $13.23 billion while the number of global daily active users stood at 1.47 billion.

In addition, the company advised at a call with analysts that it expected its revenue growth rate to be lower than the previous year.

Facebook's earnings per share, however, stood at $1.74, topping Wall Street estimates.

The world's largest social network suffered a major setback when it was involved in a data breach scandal in March after Cambridge Analytica, a British voter-profiling company, was accused of illegally harvesting the data of more than 87 million Facebook users to target political advertising.

Since then, its CEO Mark Zuckerberg has testified separately before US Congress and the European Union about his company's protection of user data.

In order to boost its profile, Facebook has introduced several changes to its advertising policy that focused on removing misinformation that incites violence or hatred.

Thursday's plunge dragged the rest of the technology sector lower, which declined about 1.5 percent in morning session.