No one walked by, or they might have called security.

But we called security and they said it was true.

He was probably running for a telephone, to call security.

Well, she could call security and tell them the document.

"Call security and see if she's come into the building."

A part of my mind wonders why he doesn't call security.

"I can also call security and have you thrown out."

For a moment, he had a strong urge to call security.

A second nurse picked up a phone to call Security.

It was also a good bet that she wouldn't have wanted to call security.