A Fourth of July parade turned dangerous when two horses pulling a carriage spooked and careened through a crowd of at least 3,000 people, killing one woman and injuring more than 20 people.

The two horses bolted and overturned their carriage during the Bellevue Heritage Day Celebration in Bellevue, Iowa, according to the Des Moines Register.

After the horses spooked, the carriage hit a sign and overturned, throwing all four of the passengers out. The horses ran for about six blocks, galloping along the sidewalk and the street where numerous children and their families had gathered to watch the parade. The horses were finally stopped after running into a parade float.

Twenty-four people were injured, with injuries ranging from cuts and bruises to broken bones. Most people were released from the hospital the same day; however, four people are still in critical condition. The wife of the carriage driver, Janet Steines, of Spragueville, Iowa, died Sunday evening.