New York: Twitter Inc urged its more than 330 million users to change their passwords after a glitch caused some to be stored in readable text on its internal computer system rather than disguised by a process known as "hashing".

The social network disclosed the issue in a blog post and series of Tweets on Thursday afternoon, saying it had resolved the problem and an internal investigation had found no indication passwords were stolen or misused by insiders. Still, it urged all users to consider changing their passwords.

"We fixed the bug and have no indication of a breach or misuse by anyone," Chief Executive Jack Dorsey said in a Tweet. "As a precaution, consider changing your password on all services where you've used this password."

The blog did not say how many passwords were affected. A person familiar with the company's response said the number was "substantial" and that they were exposed for "several months".

The disclosure comes as lawmakers and regulators around the world scrutinise the way that companies store and secure consumer data, after a string of security incidents at Equifax Inc, Facebook Inc and Uber Technologies.

The EU is due later this month to start enforcing a strict new privacy law, the General Data Protection Regulation, that includes steep fees for violators. Twitter discovered the bug a few weeks ago and has reported it to some regulators, said the person.

The US Federal Trade Commission, which investigates companies accused of deceptive practices, declined comment on the glitch. Reuters