The community in Londonderry has been left "shocked and saddened" following the death of two teenagers, a councillor has said.
The 16-year-old boys died after getting into difficulty in a lough.
The incident unfolded at Lough Enagh on Monday evening when a group of teenagers entered the water at a jetty.
The boys had stopped off at the lough while cycling in the area.
The PSNI said officers were called shortly after 6.25pm to reports of a number of people in difficulty in the water.
The Northern Ireland Ambulance Service (NIAS) said a rapid response paramedic, five emergency crews, a hazardous area response team and an ambulance officer were dispatched.
NIAS also tasked the air ambulance to attend the Bank Holiday Monday incident.
One of the boys was taken from the water but later pronounced dead in hospital.
The body of the second youth was recovered late on Monday night following extensive searches by Foyle Search and Rescue and police divers.
Another boy was taken to hospital for treatment for injuries not believed to be life-threatening, while three others have been left shocked, police said.
It is understood the families are from the local Indian community in the Waterside area.
Mark H Durkan, SDLP MLA for Foyle, posted: "Our deepest condolences and love to the families and friends of these beautiful boys.
"What an awful tragedy. Thanks to our emergency services for their heroic efforts."
Alliance Councillor Rachael Ferguson said: "My thoughts are with the family and friends of the two beautiful young boys who tragically lost their lives at Enagh Lough yesterday.
"The community is saddened and shocked by the loss of these boys. My thanks to all the emergency services who attended the scene until very late last night."
Sinn Fein MLA Ciara Ferguson said: "The thoughts and prayers of everyone in the city is with the friends and families of the two boys who tragically lost their lives at Enagh Lough, and everyone involved.
"Derry is in shock and mourning. Thank you to the emergency services for their heroic efforts."
The PSNI's Inspector Brogan said: "Enquiries are ongoing into this incident but we believe, at this stage, that this was a tragic drowning incident.
"Our thoughts are with the families of those affected."
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