And ten minutes after that, the fire alarm went off.

This must have been where the fire alarm went off.

Do you know whether it's a fire alarm or not?

It is against the law to set off a fire alarm for no reason.

The officials then pulled the fire alarm and called the police.

For all I knew, it could have been a fire alarm or something else.

She said a fire alarm in her unit never went off.

The next thing I knew, the fire alarms went off and everyone began running for the door.

That evening, before the girls can leave, a fire alarm suddenly goes off.

On 7 March, two days later, there was a third fire alarm.