Hackers have struck again at Sony Pictures Entertainment, threatening employees of the studio in a new email obtained by Variety.

The group taking credit for the hack, which calls itself “Guardians of Peace” and first hacked Sony on Nov. 24, said it planned to eradicate all of Sony Pictures Entertainment. The author of the email wrote in English and made only a single demand.

“Please sign your name to object the false (sic) of the company at the email address below if you don’t want to suffer damage. If you don’t, not only you but your family will be in danger.”

Employees were told to turn off their handheld devices after receiving the message, according to insiders at Sony.

“We are aware of the situation and are working with law enforcement,” a spokesman said in a statement.

On Thursday, North Korea denied its involvement in the ongoing data breach after media outlets said the attack was a response to Sony’s new movie “The Interview,” in which Seth Rogen and James Franco attempt to assassinate North Korean dictator Kim Jong-un.

“Linking the DPRK (Democratic People’s Republic of Korea, the official name of North Korea) to the Sony hacking is another fabrication targeting the country,” an unidentified North Korean diplomat told Voice of America on Thursday. “My country publicly declared that it would follow international norms banning hacking and piracy.”

Over the past two weeks, Sony Pictures Entertainment has been plagued by headaches stemming from the massive security breach. Personal information of its 3,803 employees has leaked online along with a spreadsheet purportedly listing salaries of top studio executives, and five of the studio’s films, including “Annie” and “Still Alice,” turned up on the Internet, where they have been widely pirated.

The security breach dates back to Nov. 24, when Sony Pictures employees logging on to the company’s network were greeted with an image of a skeleton and a message that said, “Hacked by #GOP.”

Sony has been working with law enforcement officials, including the FBI, to investigate the cause of the data breach and has hired security firm FireEye and its Mandiant unit to look into the incident.

The FBI released a statement following Friday’s email: “The FBI is aware of threatening emails that have been received by some employees at Sony Pictures Entertainment. We continue to investigate this matter in order to identify the person or group responsible for the recent attack on the Sony Pictures network. Recent events underscore the persistence and maliciousness of harmful cyber criminals, and the FBI will continue to identify and apprehend those who pose a threat in cyberspace.”

Read the “Guardians of Peace” email in full:

I am the head of GOP who made you worry.

Removing Sony Pictures on earth is a very tiny work for our group which is a worldwide organization. And what we have done so far is only a small part of our further plan. It’s your false if you think this crisis will be over after some time. All hope will leave you and Sony Pictures will collapse. This situation is only due to Sony Pictures. Sony Pictures is responsible for whatever the result is. Sony Pictures clings to what is good to nobody from the beginning. It’s silly to expect in Sony Pictures to take off us. Sony Pictures makes only useless efforts. One beside you can be our member.

Many things beyond imagination will happen at many places of the world. Our agents find themselves act in necessary places. Please sign your name to object the false of the company at the email address below if you don’t want to suffer damage. If you don’t, not only you but your family will be in danger.

Nobody can prevent us, but the only way is to follow our demand. If you want to prevent us, make your company behave wisely.