Google seems to have been hit by a global login outage which seems to have affected Gmail and Google Docs. There were problems signing in to Google products from the US, UK, India, Singapore, and Europe to Australia. Read more at theguardian.com
This problem was said to last for around two hours which began around 11pm BST. The company is said to be investigating the issue with OAuth login and also an issue with Admin console.
Some users were greeted with an error page while they were trying to login and there was a cited error 502 and it asked them to try again in 30 seconds.
Google claims that it is said to conduct an internal investigation of the issue and will make appropriate improvements to their systems for helping to prevent and minimise recurrence.