IOWA — It was a deadly Thanksgiving travel period in Iowa last week.

According to the Iowa State Patrol, its troopers responded to 54 crashes. From last Wednesday to this past Sunday, seven people were killed in traffic-related fatalities.

Officials say there are several causes: driver error, speeding, passengers not wearing a seat belt, and alcohol.

They say alcohol consumption was up during the Thanksgiving holiday.

“And we did arrest a number of drivers for driving while impaired. We actually arrested 35 people for driving while impaired. That’s 35 people that could have led to another fatality or serious injury crash. That doesn’t have to happen. But unfortunately, we did see 12 people here over the last week killed in the state of Iowa,” said Sgt. Alex Dinkla with the Iowa State Patrol.

According to the Iowa DOT, as of Monday, there have been 315 traffic-related deaths this year. In 100 of the deadly crashes, the victim was not wearing a seatbelt.