DES MOINES, IOWA -- More than 100 piglets died Thursday when a semi-trailer carrying about 1,700 of the animals overturned on a freeway just north of Des Moines.

Tom Colvin, chief executive officer of the Animal Rescue League of Iowa, said Friday about 100 piglets were found dead at the crash site. Crews had to euthanize another 17 that were injured.

"They were suffering," Colvin told The Des Moines Register.

The crash happened Thursday afternoon when a livestock trailer overturned on a ramp to Interstate 35.

The surviving animals were loaded onto other trucks and driven to a livestock operation.