An 18-year-old girl's body was pulled from Douglas Reservoir in Douglas, Massachusetts on Saturday afternoon, according to Douglas Police.
Annie Krantz, of Oxford, Mass., was swimming with a group of friends when she went missing at about 2:15 p.m.
Douglas Deputy Fire Chief John Furno said that one friend "stated that she started to struggle a little bit and went under. They frantically tried to rescue her; they were unsuccessful."
At that point, one person left the water and called 911.
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Krantz's body was recovered around 2:45 p.m. by a dive team in about six feet of water.
She was brought to Harrington Hospital where she was pronounced dead.
"There's no swimming allowed but they still go ahead and swim," Furno said of the reservoir, located in a 5-thousand acre state forest.
"There was a rope swing that was cut down last year. They were in that area, swimming."
Until her death, Krantz attended Oxford High School. OHS Principal Ross Thibault said in an email to NBC Boston that "the school was open today from 9:00 a.m. until 1:00 p.m. [Sunday] during which time the Oxford High School administrative and counseling teams met with students and staff who were still coming to grips with this sudden loss."
Thibault expects that the counseling staff will be available during the rest of the week, starting Tuesday, "for any student or staff member in need of support."
He said that several students brought flowers to the school and there are currently several suggestions concerning how to honor Krantz during Senior Week at the school.
At this time, an investigation into Krantz's death is still underway.