Health officials are investigating claims that terminally ill children have been illegally euthanised by British doctors.
An official investigation has been launched by the Department of Health into the allegations, Health Secretary Jeremy Hunt said.
In February, retired GP Michael Irwin claimed that medics have given sick children overdoses with painkillers.
After being asked about the issue on LBC Radio, Mr Hunt said: "An investigation is now under way by my department.
"The police are not involved at the moment. I'm afraid I am not in a position to comment because it is highly sensitive."
Euthanasia is illegal in Britain but legal in other countries. In February, Belgium became the first country in the world to allow the euthanasia of children.