Scott Collins, 17, of Chesterton, Indiana just missed being caught up in a potentially fatal collision on I-94. He and three teenage companions witnessed a series of pile-ups occur behind them on Thursday, which began with a number of semitrailers sliding on the snowy roadway. The incident took place near Michigan City and approximately 60 miles away from Chicago.

Says Collins about what he witnessed, “One of the semis started sliding and I think it jackknifed in the middle of the road and collided with another semi. After that happened, multiple semis locked up.” He admits he and his friends were “pretty nervous” they would be caught up in the ensuing chaos, which thankfully didn’t happen.

Others were not as fortunate.

The massive pile-up involved over 40 vehicles, including 18 semitrailers. The cars were crushed among the sliding semis resulted in more than 20 people being hospitalized with injuries. Indiana State Police Sgt. Ann Wojas says at least one person had to be air-lifted from the scene with life-threatening injuries. 3 individuals and a pet dog were killed as a result of the crash.

URGENT RT! Lost family dog ejected from vehicle during WI major accident in snowstorm! http://t.co/Ior6R38Amw @Dontignoretruth @ROwazany

— Marilyn (@chenoite) December 9, 2013

Two of the individuals as identified by LaPorte County coroner John Sullivan were 67-year-old Thomas Wolma and his wife Marilyn, 65, of Grand Rapids, Michigan. According to their son, the couple had been returning home from caring for a family member in living in Wisconsin.

The third person killed was 65-year old Jerry Dalrymple of Chicago, Illinois. His dog also died in the crash.

The accident resulted in backed up traffic on Thursday afternoon into the evening as traffic was forced to a standstill, leaving confused drivers to sit in freezing temperatures for hours.

The eastbound lane of I-94 remained closed on Friday morning. Cpl. Larry Koebcke said that crews were continuing to work to clean up the scene of the pile-up and officials are uncertain how long the cleanup effort will actually take and when the lanes will reopen to traffic.

Image via NBC Chicago’s Twitter