A promotional party held by Jägermeister in Leon, Mexico on Saturday turned tragic after party organizers poured liquid nitrogen into a swimming pool, creating a toxic brew that put one man in a coma and sent eight others to the hospital, the UK Mirror reported.

The liquid nitrogen created a noxious fog that hung over the pool area and rendered many partygoers unable to breathe. Several quickly became unconscious and were in danger of drowning, according to the Mirror.

“They realized that I had fainted because they saw the tray floating alone in the pool,” Jael Jimenez, a hostess at the party, told Milenio.com, according to the Mirror. “Otherwise, I might have drowned.”

A 21-year-old attendee, identified by Univision Noticias as Jose Ignacio Lopez del Toro, is now in a coma in intensive care. Eight others were reportedly hospitalized and are being treated.

The liquid nitrogen was intended to create a smoke effect in the pool.

A spokesperson for the popular German liquor company said:

“We are aware of this incident in Leon, Mexico, which is currently being investigated by our headquarters in Germany. Fortunately, all of those who required medical attention are out of danger and recovering.

“We are liaising with our responsible distributor in Mexico who is working with the event organisers and the investigating authorities to understand the full circumstances surrounding the events last Saturday night.

"We fully support responsible drinking and adhere to the guidelines within each market in which we operate.”

The local attorney general is investigating, according to Mexican newspaper El Universal.

A video of the party was posted on YouTube. Some screenshots and the video are below.