An Angel Flight New England (AFNE) plane crashed in a supermarket parking lot here Tuesday morning killing the pilot, a cancer patient and his wife. There were no casualties on the ground.

Witnesses saw the single-engine plane stalling before nose-diving at the Hannaford's parking lot on Robert Drive near Route 106 at 10:25 a.m. The plane exploded into a fireball.

"We could see there were people inside [the plane], but there was nothing you could do. It was horrible. We watched them burn ... we felt helpless," Darcy Stillman, the manager of the Tanfastic Tanning Salon in the shopping plaza, recounted to Boston.com.

The pilot may have deliberately maneuvered the plane to the parking lot to avoid casualties, according to Easton Fire Chief Thomas Stone.

Janet Keene, the owner of the four-passenger Beechcraft Bonanza, identified the dead pilot as family friend Joe Baker of Brookfield, CN. The dead passengers were from Long Island but their names were withheld.

The AFNE plane took off at 9:10 a.m. from an airport in Westhampton Beach, NY, and was heading to Logan International Airport where the patient was to be taken to the Dana-Farber Cancer Institute in Boston for cancer treatment.

AFNE spokeswoman Amy Camerlin said the crash was the first in the 12-year existence of the organization of volunteer pilots who help needy patients get medical care.