Facebook Inc.'s WhatsApp messaging service resumed in Brazil on Tuesday after an appeals court overturned a suspension and many of the application's 100 million users in the country voiced outrage.
WhatsApp was cut off in Brazil at 2 p.m. (17:00 GMT) Monday after a judge in the remote northeastern state of Sergipe ordered Brazil's five main wireless operators to block access to the app for 72 hours. The reason for the order was not made public, and it was the second such freeze in five months.
The suspension was lifted after about 24 hours when an appeals judge Tuesday ruled in favor of an injunction by WhatsApp's lawyers, the court said in a statement.
The suspension highlighted growing international tensions between technology companies' privacy concerns and national authorities' efforts to use social media to gain information on possible criminal activities.
The same judge in Sergipe ordered the imprisonment of a Brazil-based Facebook executive in March in a dispute over demands to access the company’s encrypted messaging service as part of a drug trafficking investigation.
California-based WhatsApp had said in a statement on Monday that it was "disappointed" at the judge's decision to suspend its services. It said it had done the utmost to cooperate with Brazilian tribunals, but it did not possess the information the court was requesting.
The company has said in the past that it does not store encrypted information from WhatsApp messages.
A São Paulo state judge ordered text message and Internet voice telephone service for smartphones be shut down for 48 hours on Dec. 15, after Facebook failed to comply with an order, although another court interrupted that suspension shortly afterward.
Monday's suspension angered many in Brazil, where more than 90 percent of Android devices have WhatsApp installed. Cost-conscious Brazilians are avid users of free messaging apps, and WhatsApp is by far the most popular.
The service is used by individuals, companies and federal and local governments to send messages and share pictures and videos.
As some Brazilians sought an alternative messaging system, rival Telegram said on Monday that it suffered technical problems under the weight of demand. It said it received more than a million new user requests.
Letícia Mendes, a 20-year-old shop assistant in Rio de Janeiro, said she was frustrated by the suspension because it could force people to use pay services.
"It's really bad because some people only look at WhatsApp on their phones, so now they take a long time to answer," she told Reuters. "It's just a way of getting more money out of us, when we already have to pay for so many things."
The suspension came as a congressional commission on cyber crime in Brazil debated changes to the 2014 legislation governing the use of the Internet.
Lower house deputy Esperidião Amin, the rapporteur of the commission, said his proposed reform would help avoid shutdowns of this kind by allowing the blocking of specific individuals or IP addresses suspected of illicit activity, rather than the access of all users.
"It's less dramatic than withdrawing the service from the whole of the Brazilian population," he told Reuters by telephone.