The pop star's Dassault Falcon 990 was en route to Minnesota when pilots requested an emergency landing about 1:15 a.m. last Friday, says Jeff Patterson, the public safety manager at the Quad-City airport in Moline, Illinois.
"We had an emergency landing for an unresponsive person," he says.
"The call came in from the control tower – the FAA control center – that the plane had an unresponsive person on board. They needed an emergency landing and requested an ambulance."
Prince's rep confirmed to PEOPLE last week that the star's plane made an emergency landing in Moline so the singer could be taken to a local hospital. The rep also said the Purple Rain icon had been battling the flu for weeks.
Patterson could not confirm a TMZ claim that Prince was given a "save shot" after allegedly overdosing on the prescription painkiller Percocet. E! News also reports that the star had been taking the powerful drug.
A source told PEOPLE on today that Prince was struggling with a "serious illness." "The people close to him were very concerned for his health and indicated he'd been undergoing treatments which made his immune system weak," the source said.
Prince's rep told PEOPLE he was released after three hours, and Patterson confirms the plane took off again around 11:30 a.m.
Prince's scare happened just after the singer performed in Atlanta as part of his Piano and a Microphone tour. The April 14 performance was postponed from the previous week due to the singer's illness.
After the emergency landing, Prince was active on Twitter – even sharing a tweet that included the hashtag #FeelingRejuvenated.
The legendary musician died just four days later after he was found unresponsive in an elevator in his famed Paisley Park estate.