A 16-year-old girl from Wellesley died after her body was discovered submerged in an icy pond in Andover.

Elizabeth Mun was last seen around 5 a.m. Sunday at a sleepover party on a William Street home.

She later left the house on foot and her friends went out searching for her. Authorities were called two hours later after efforts to find her failed.

Mun was found in a pond and was taken to Children's Hospital in Boston, where she was pronounced dead at 5:27 p.m.

Mun's school, the Concord Academy, released a statement mourning her death and describing her as an independent thinker with a finely tuned sense of humor.

Police are investigating the incident.