An MP called for an inquiry today after two teenage girls jumped from a bridge in an apparent suicide pact.
Neve Lafferty, 15, and Georgia Rowe, 14, leapt more than 100ft from the Erskine Bridge, near Glasgow - hours after spending a "happy" weekend with relatives.
They were reportedly holding hands as they plunged into the River Clyde at the notorious suicide spot on Sunday night.
Neve was grieving for her boyfriend who died from a drug overdose, according to reports.
Both girls were pupils at the Good Shepherd Centre in Bishopton, Renfrewshire - an independent unit owned and managed by its own voluntary board of managers.
Argyll and Bute Council said it would launch an investigation into the circumstances surrounding the "distressing case".
Local MP Jim Sheridan called for an inquiry into how the two girls were able to leave the unit unsupervised.
He said: "The relatives and friends of these young girls will be suffering unimaginable horror and grief.
"They will want to know exactly what happened and why a tragedy of this nature took place.
"It is important to see both an internal and police inquiry to answer questions and explain the events.
"People here really are in shock that something so terrible could happen.
"My heart goes out to all those touched by this."
Mr Sheridan also said the Good Shepherd is a "fine organisation".
The centre has three sections - an open unit, a secure unit and the St Francis Day Unit.
The two girls who died were among nine live-in residents at the open unit, which also has 21 day girls who live in foster or care homes.
Pupils there are not supervised around the clock but any outing requires authorisation.
No authorisation was given for the girls to leave on Sunday evening.
A centre spokesman said they had been on "apparently happy and productive" weekend outings with relatives and were seen by staff in their pyjamas going to their rooms to watch television.
The two girls apparently sneaked out of the centre shortly before 9pm and made their way to the nearby bridge before jumping to their deaths side-by-side.
Staff carrying out routine checks noticed they were missing and began a search of the campus and the immediate vicinity.
The unit cares for young girls referred to the centre by local authority educational and psychological services, social work departments and children's hearings.
The girls came to the unit seven to eight weeks ago.
Tributes were also paid to the two girls on their respective Bebo website pages.
A message on Neve's Bebo page from Josie Killen Mate said: "Cant believe you are gone hunni,I miss you. All the good times we have had.. Ill be thinking of you always..
"R.I.P babe gone but never forgotten. iloveyou."
David Rowe wrote on Georgia's Bebo page: "georgia a know we havent spoke in a very long time but u'll always be ma wee cousin an a love u
"hope ur in a better place now. R.I.P"
Dawn McMahon Blackhurst also wrote: "Aw wee pal. Im so sorry it came to this. youll be very muched missed. I cany believe am actually having to write this. ill never forget your wee cheeky smile n such a beautiful wee face. Im sorry pal.
"Ill think of you always. Lots of love Dawn (and a big kiss fi wee Jai)."
Nigel Richardson, chairman of the Hull Safeguarding Children Board, said it was working with the authorities in Scotland to find out what had happened.
He said: "Our sympathies go out to the friends and family of both of the young women."
An Argyll and Bute Council spokeswoman said: "We will be holding our own investigation into the circumstances surrounding this distressing case, and will of course assist other agencies in any way we can during their inquiries."
Strathclyde Police said there appeared to be no suspicious circumstances surrounding the deaths.
Mr Sheridan also called for more security measures to be installed on the bridge.
"There are far too many deaths," he told BBC Radio Scotland's Good Morning Scotland.
"I think we need to look at some sort of fencing that stops people from doing this.
"People who live in the area of the Erskine Bridge know when someone's jumped off the bridge because they hear the helicopter.
"On Sunday night, I heard the helicopter.
"It's happening too often, too regularly.
"I think we need to look at some sort of security measures on the bridge to stop this from happening."