Carver County Chief Deputy Jason Kamerud told Fox 9 that they responded to a medical call at 9.43 am. The cause of death is not yet clear.
The iconic singer, real name Prince Rogers Nelson, was hospitalised after his jet made an emergency landing on Friday morning.
A spokesperson later said he was suffering from the flu prior to the performance and that the plane landed at Moline so he could receive treatment there. Prince later flew on and returned home.