How did these people die? I saw this in my local news blog this a.m., it caught my

[Nitram]

6. True. I'm surprised, though, that the concentration indoors could get high enough to kill people.

A nearby school could never have felt the effects once it dispersed into the atmosphere.

I found the following at the link below:

Nitrogen gas can cause suffocation without warning. Store and use liquid nitrogen only in a well ventilated place.

As the liquid evaporates, the resulting gas tends to displace the normal air from the area. In closed areas, excessive amounts of nitrogen gas reduce the concentration of oxygen and can result in asphyxiation. Because nitrogen gas is colorless, odorless and tasteless, it cannot be detected by the human senses and will be breathed as if it were air. Breathing an atmosphere that contains less than 19 percent oxygen can cause dizziness and quickly result in unconsciousness and death.

https://www.tedpella.com/cryo-supplies_html/HandlingLiquidNitrogen.htm