Sony could face an inquiry and legal action by the UK and the US governments for hiding the massive data breach that hit its Play Station network (PSN) last week, which the company now says could affect over 77 million users worldwide.

On 19 April, the Japanese electronics maker shut down its PSN, but the company did not disclose the data theft. It said that the service was being fortified for additional security of users.

Sony had said that it had turned off the service as it was investigating an "external intrusion" and upgrading its security with additional features.

"Though this task is time-consuming, we decided it was worth the time necessary to provide the system with additional security," the company said.

"We thank you for your patience to date and ask for a little more while we move towards completion of this project."

Online hacktivist group Anonymous had also said that it was not responsible for the outage.

However, a week later, Sony said the service had been hacked and that hackers could have accessed personal details, including credit card details, of 77 million users spread across the world.

A Sony spokesman said that it took"several days of forensic investigation" to find out that consumers’ data had been compromised.

The disclosure led to outrage among users worldwide and shares in Sony fell 5%.

The delay is being seen by many as an attempt to deliberately hide facts from consumers. Governments in both the US and the UK have taken note of the issue and have asked Sony to explain.

In the US, Senator Richard Blumenthal has written a letter to Sony saying that it was slow in notifying PSN users of the breach and loss of their personal data.

Several Congress members are pushing for stricter laws aimed to protect personal data in the country. The staff of a House of Representatives subcommittee were directed to investigate the PSN data breach.

Meanwhile in the UK, the government’s Information Commissioner’s Office (ICO) has contacted Sony over the breach. The watchdog will also start an investigation to find out suitable action that could be taken by the government on behalf of the 3 million UK PSN users.

The ICO said, "We have recently been informed of an incident which appears to involve Sony. We are contacting Sony and will be making further inquiries to establish the precise nature of the incident before deciding what action, if any, needs to be taken by this office."