The sentence is correct and usable in written English. You can use the phrase when referring to a person or thing being threatened with death. For example: "The main witness in the case is under threat of death.".
Haines, a Scots aid worker, who has two daughters, aged 17 and 4, is under threat of death from the hands of Islamic State.
He said if Kurds were "under threat of death and terrorism" then Iraqi Kurdistan would be "prepared to defend them".
Children who did not perceive themselves to be under threat of death during the cyclone were more likely to belong to a family rated by parents as dysfunctional.
But the Jewish community in Iran is not under threat of death.
The patrollers say they, too, are victims, contending that they were forced under threat of death to leave their farms and villages to work with the army to rout leftist guerrillas.
To offer a special 15th-century version of the Kaddish, a prayer for the dead that was once forbidden under threat of death and was delayed for 320 years.
They cannot do so if they are under threat of injury, abduction, harassment, arrest or even death," said Owusu.
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