Authorities in Taiwan say they are looking into a ransomware cyber-attack on a major technology firm there.
Quanta Computer is a manufacturer of many flagship Apple products, including its MacBook line.
The hackers, known as Revil, have published stolen blueprints for unreleased products, and are threatening to release more.
Taiwanese officials said they are "taking an initial step to look into and understand" the incident.
It is being handled by the Ministry of Justice's investigation bureau.
On their darknet website, the anonymous hackers are attempting to extort a ransom from Apple directly, writing: "We recommended that Apple buy back available data by 1 May."
It is understood they are asking for tens of millions of pounds.
Apple has not responded, but Quanta confirmed a cyber-attack had taken place.
In a press release, the company said: "Quanta Computer's information security team has worked with external IT experts in response to cyber-attacks on a small number of Quanta servers.
"We've reported to, and kept seamless communications with, the relevant law enforcement and data protection authorities concerning recent abnormal activities observed. There's no material impact on the company's business operation."
The release of the hacked material came just hours before Apple's major product showcase event on Tuesday.
Revil said the timing was not a coincidence, writing that the data leak was "in order not to wait for the upcoming Apple presentations".
The Taiwanese Investigation Bureau, under the Ministry of Justice, told Nikkei Asia: "We are aware of an alleged cyber-attack involving Quanta and we are taking an initial step to look into and understand the nature of the incident.
"But we have not yet opened a case and launched an official probe."
The Revil group - also known as Sodinokobi - is one of the most prolific and profitable cyber-criminal cartels in the world.
The gang has previously hacked and extorted foreign exchange company Travelex, and New York law firm Grubman Shire Meiselas & Sacks.