Actress Kirstie Alley sparked outrage on social media Monday when she suggested "psychiatric drugs" may have contributed to the uptick of mass shootings in the U.S. in recent years.

"We have to solve the mystery of Why there were no 'shooters' or almost 0 before the 1980's," Alley wrote on Twitter. "I know one common denominator other than guns."

We have to solve the mystery of Why there were no "shooters" or almost 0 before the 1980's.I know one common denominator other than guns — Kirstie Alley (@kirstiealley) October 2, 2017

Alley, who starred in NBC hit television show "Cheers," then said the common dominator in these tragic incidents was "the USA's mass usage of psychiatric drugs."

"A % do have side effects of VIOLENCE & SUICIDE," she tweeted.

One additional common denominator of "shooters" is USA's mass usage of psychiatric drugs. A % do have side effects of VIOLENCE & SUICIDE. — Kirstie Alley (@kirstiealley) October 2, 2017

Alley's comments follow a night of violence on the Las Vegas Strip when 64-year-old Stephen Paddock opened fire on a crowd of concertgoers attending the Route 91 Harvest country music festival from the Mandalay Hotel, killing 59 people and injuring more than 500.

There's no evidence at this point that Paddock was using prescription drugs of any kind.

Alley's post provoked anger and intrigue on social media.

"Did you really just say that? Sit down. 58 people are dead," Florida-based ABC reporter Derek Shore wrote.

"Yes I did say it," Alley responded."[N]ot my opinion. Statistic based."

Yes I did say it. It happens to be a common denominator in shooters..one that didn't exist before the 80's.. not my opinion. Statistic based https://t.co/M7zopL4Dwl — Kirstie Alley (@kirstiealley) October 2, 2017

Alley said she had the "utmost sympathy" for the victims of the attack and their loved one but that the conversation is not had and, therefore, solutions weren't found.

"Prayers & condolences aren't enough anymore," Alley added.