It is, to say the least, a highly unusual situation.

In 2002 the world learned about a highly unusual court case.

None has been held, which is highly unusual in itself.

It seems highly unusual that only part of the story is told.

A television campaign this far before an election day is considered highly unusual.

This was a highly unusual step, which had not been taken for many years.

Using regular military forces in such a situation would be highly unusual.

Even so, American officials said this was a highly unusual step.

It was highly unusual for so many people to be there that early.

The fact that they are being brought to justice at all is highly unusual.