Facebook, Instagram and WhatsApp services resumed after being shut down for seven hours.
WhatsApp, Facebook and Instagram services all over the world, including Pakistan, remained closed for several hours, during which millions of users faced difficulties.
WhatsApp service in Pakistan was shut down at around 8:45 pm on Monday night.
Experts say the reason for the closure of Facebook is not yet known, it is premature to say that a cyber attack has taken place.
Website security company says services are missing from the Internet due to a traffic routing error.
According to media reports, Mark Zuckerberg, the owner of the companies, has lost 7 billion dollars (about 12 trillion Pakistani rupees) in 7 hours due to the closure of services.
According to foreign media, Facebook shares have fallen by 4.9%. Similarly, in US markets, the Nasdaq is down more than 2%.