Police continue to investigate a single-vehicle car crash that killed an Algonquin woman and injured three others on Tuesday night west of Huntley.

Megan E. Hartigan, 20, of Algonquin died at Centegra Hospital – Woodstock shortly after the wreck off the 1400 block of Marengo Road in unincorporated Coral Township.

Hartigan and three others were traveling west on the road in a 2004 Hyundai Elantra when the car veered into a ditch, struck a culvert and flipped, ejecting the four occupants, according to the McHenry County Sheriff's Office.

Officials at the scene said that it appeared the victims were not wearing seat belts at the time of the crash.

"They were thrown quite a distance," Marengo Fire Chief Robert Bradbury said. "At least two patients were quite a ways off the road."

Two of the car's occupants, Jonathan J. Lombard, 21, of Huntley, and a juvenile, were taken to Sherman Hospital in Elgin, according to a press release from the McHenry County Sheriff's Office. Lombard was listed in critical condition late Wednesday, a hospital spokeswoman said.

Another, Ryan W. Hanks, 18, of Huntley, was taken to Provena St. Joseph Hospital in Elgin. A Provena representative declined to release information about Hanks' condition Wednesday night at the request of his family.

Investigators were still trying Wednesday to determine who was driving the car. Sheriff officials are looking for any possible witnesses of the crash to come forward with information.

The McHenry County Coroner's Office determined during an autopsy Wednesday that Hartigan died from head and chest trauma after the crash. Results from a routine toxicology test are pending.

Hartigan, a 2010 graduate of Jacobs High School, was remembered by school officials as a friendly student who enjoyed socializing with friends.

"She was fun-loving and always had a bright smile," Principal Ami Engel said.

Tuesday's crash is the second fatal accident to occur in the area in recent months.

Jennifer M. Kearns, 19, of Huntley, was killed in February just 2 miles west in the 17500 block of Marengo Road in unincorporated Coral Township.

Kearns was a passenger in a Jeep Cherokee headed west on Marengo Road about 8 p.m. Feb. 22 when the vehicle went into a ditch on the north side of the pavement, struck a tree, rolled over, and came to rest on its side, officials said.

Kearns was thrown from the vehicle and was pronounced dead at the scene.

At least two other passengers were injured, and, according to the sheriff’s office, none of the Jeep’s four occupants were wearing seat belts.