Liz Hinckley was on the T-bar lift, parallel to the Spillway East lift, and arrived at the scene moments after the accident.
She told ABC News the skiers were "very calm, and the rescue crews got there very quickly. It was very cold, and there were some young kids who were fairly high up," when the lift came to a halt.
Franklin County Emergency Management told ABC affiliate WMTW that officials received word of a "condition yellow," which means people were injured, not critically.
A spokeswoman for Franklin Memorial Hospital in Farmington, Maine, said eight of the injured were being taken there by ambulance, including some children. The hospital is 45 minutes from the ski area. One of the injured was later taken by helicopter from Farmington to Maine Medical Center in Portland for treatment.
Jay Marshall, who was on a lift next to the broken one, told the AP that both lifts stopped, then restarted. Almost immediately he saw a problem, then heard screams.
"The lift started again. I looked to my left and could see the cable bouncing up and down. I could see that the cable had come off the (track wheels)," he said. "It was terrifying."
The Spillway East chairlift is 4,013 feet long. It was installed in 1975 and modified in 1983. It moves at a speed of 500 feet per minute, and the chairs are 50 feet apart.
According to state records, it was last inspected by the Maine Office of Licensing and Regulation on Oct. 20, and was not due to be inspected again until Nov. 30, 2011.
Sugarloaf said the chairlift receives routine daily inspections, as well as weekly, monthly and yearly maintenance and testing.
On its website, Sugarloaf said the Spillway life "is ... vulnerable to wind holds," and that improvements are underway to improve the mechanism.
The Associated Press contributed to this report