The phrase "an undisclosed cause" is correct and usable in written English.
It can be used when referring to a reason or factor that has not been revealed or made public.
Example: "The investigation was halted due to an undisclosed cause that raised concerns among the officials."
Alternatives: "a hidden reason" or "an unknown factor".
PAGE C5 EXPECTING A QUIETER FOURTH An explosion (of still undisclosed cause) that destroyed 20 fireworks warehouses in China three months ago led to a ban on fireworks shipments at all but two Chinese ports.
On Oct. 28, 2014, Zambia's president, Michael Sata, died in a London hospital of undisclosed causes.
He was 93. Lee died in London of undisclosed causes, according to an official with the Royal Borough of Kensington and Chelsea in London, who spoke on condition of anonymity in keeping with the policies of the borough.
That is why the death last week from undisclosed causes of another American on the tour, Erica Blasberg, hit Kerr with the emotional blunt force of a flashback.
In October 2014 Koum donated roughly $555 million of Facebook shares to the Silicon Valley Community Foundation, which provides grants for local needs, and has anonymously diverted some of the funds to several undisclosed causes.
Norman Farberow, one of the founding fathers of modern suicidology and suicide prevention, died last week of undisclosed causes.
The fighter born Kevin Ferguson had been hospitalized for undisclosed causes near his home in Coral Springs, Fla., according to reports. .
A photographer who broke new ground in advertising before he became famous for his evocative celebrity portraits, Stern, 83, died Wednesday at his New York City home of undisclosed causes.
Slice, whose real name was Kevin Ferguson, was hospitalized Monday for undisclosed causes near his home in Coral Springs, Fla., according to reports.
According to the complaint in a case that J&J has settled for an undisclosed sum, Tylenol poisoning caused her liver to fail.
