The Sept. 11 Museum officially opened to the public Wednesday, but victims' families are outraged at what happened there Tuesday night.

Museum officials confirmed they held a small party in the museum Tuesday night with about 40 to 50 people in attendance. The party was held for private donors who sponsored the five days of previews that began last week.

According to published reports, the atmosphere at the party was festive and alcohol was served.

First responders, such as Anthony Flammia, told News 12 that throwing a party at Ground Zero is “disgusting.”

Flammia says he's heard of reports that some Sept. 11 responders and their families who were invited to the party were told to leave early in favor of VIPs.

The museum would not confirm if alcohol was served or if any firefighters and other first responders were kicked out early.