A pair of siblings died Saturday afternoon when a vehicle struck a Monroe County, Michigan building where a children’s birthday party was taking place.

An 8-year-old girl and 5-year-old boy were pronounced dead on scene after a woman drove a vehicle into a Monroe County boat club around 3 p.m. on Saturday, said county Sheriff Troy Goodnough in an evening press conference.

Fifteen other people were injured in the incident, Goodnough said.

Three children and six adults were taken by medical helicopter or ambulance with “serious, life-threatening injuries,” Goodnough said. Six others were taken to the hospital by private vehicles.

It is unclear how many people were inside the building at the time, police said.

“The scene was described by the first responders as extremely chaotic, with high level of emotions of those directly involved and those who witnessed this horrific incident,” Goodnough said.

Police were called to the Swan Creek Boat Club, 6332 Brancheau St. in Berlin Township, after an unnamed 66-year-old woman crashed a vehicle into the building, sending it roughly 25 feet inside the building.

The woman was arrested for operating a vehicle while intoxicated and is currently being held in the Monroe County Jail. A restaurant that police suspect the woman visited earlier that day is temporarily closed while police investigate, Goodnough said.

The woman will likely face criminal charges, he added.

A representative of the Swan Creek Boat Club declined to comment to the media. The social club did say on its Facebook page that it will be closed Sunday, and posted a message about the incident: “There was a terrible accident at Swan today with many injuries, and much damage to the pavilion. Please keep all the people and families in attendance in your prayers.”