A 26-year-old woman was killed and four other people were seriously injured after a collision between two recreational boats Thursday night on Lake Michigan near downtown Chicago.

The victim was identified as Johanna H. Gregory, a resident of the West Loop area and originally from Rochester, New York, according to the Cook County Medical Examiner's Office.

The accident occurred near Monroe Harbor around 11:45 p.m., when two boats carrying a total of 14 people were returning to port, the Chicago Tribune reported.

Five people were taken to hospitals

According to the Chicago Fire Department, five people were taken to hospitals with injuries considered serious to critical.

Nine occupants refused medical attention.

Authorities indicated that one of the boats was transporting nine people and the other five.

During the collision, two occupants fell into the water, but were rescued by people on board before emergency crews arrived.

Three injured people were taken to Northwestern Hospital and two others to Stroger Hospital.

Authorities investigate how the impact occurred

Preliminary information indicates that both vessels were returning to port when one overtook the other and the collision occurred approximately a mile and a half from the coast.

Chicago Fire Department Deputy District Chief Jason Lach described the incident as a high-impact collision.

However, authorities said they have not yet determined exactly how it happened.

They have also not reported who operated the boats or if factors such as speed, alcohol consumption, drugs, navigation lighting or use of life jackets were related to the accident.

Authorities indicated that the conditions of the lake do not appear to have influenced the incident.

Family and university remember the victim

Gregory worked as a pediatric occupational therapist, caring for children between six months and four years old.

Her mother described her as an empathetic person and committed to the families she accompanied.

Gannon University, where she played volleyball, also issued a message remembering her as a valued member of its community.

The investigation was carried out by the Illinois Department of Natural Resources.

So far, no penalties or charges related to the accident have been announced.