Police and health services in south Wales have set up a group aimed at preventing more suicides in Bridgend and the surrounding area.
Last week Natasha Randall, 17, was found hanged at her home at Blaengarw, near Bridgend, and a girl believed to know her self-harmed a day later.
Seven young people have committed suicide in the past year in the area.
Officers are investigating whether the girls had made contact on the internet, by e-mail or on a networking site.
Police also said they had spoken to a number of young people and parents to urge them to be vigilant.
South Wales Police have joined a focus group, which also includes members from Bro Morgannwg Health Trust, local schools and Bridgend Council, to help prevent suicides and attempted suicides.
Supt Tim Jones, divisional commander of police at Bridgend, said they were looking at the circumstance surrounding Natasha's death.
"It is important to stress that at this time we have not established any direct links between [this] death and a 15-year-old girl attempting to harm herself in Pontycymmer on Friday.
"However they were known to each other as you would expect in small neighbouring communities," he said.
"One line of inquiry within the investigation is the examination of the computer of the 17-year-old girl which is currently ongoing.
"Clearly communication between friends and associates is an important consideration.
"There is a growing trend for young people to communicate through telephone text messaging and also over the internet whether it's e-mail or within chat room forums."
Last summer, Bridgend coroner Philip Walters said he was "desperately concerned" about the number of suicides among young men in the Bridgend and south Wales valleys area.
One of those was 20-year-old Thomas Davies from North Cornelly, who hanged himself in February 2007. He had been friends with two other young men, David Dilling, 19, and Dale Crole, 18, who had been found dead weeks earlier.
Thomas's mother, Melanie Davies, said she had talked to her son about the deaths of his friends: "He was quite upset about Dai [David Dilling] because he went to school with him.
"I said to him: 'You would never do that to me, would you?'.
"He said: 'I'd never do that to you - I wouldn't hurt you mam'. I think it was a couple of days later that he did it."
Mrs Davies has urged young people to seek help.
"I think they should talk to somebody, even if it's a stranger. They really need to speak to somebody, even if it's over the phone."
Darren Matthews, branch director of the Samaritans charity in Bridgend, said there had been a "marked increase" in the suicide rate among young people over the past year, adding they had heard reports of at least one suicide a month.
His organisation has been involved for over a year with a suicide prevention group, and has also been holding meetings with the local MP Madeleine Moon on the issue since June.
"The problem is young people think their problems are too trivial. We need to get the message across that they can contact us about anything they want.
"Madeleine was instrumental in setting up what we call coffee-and-a-chat sessions to get young people to come along and chat, whether about moving from home to university, families, whatever," Mr Matthews said.
Asked whether he thought modern technology could be adding to the problem, he said: "The internet is a method of communication that has been used for some time and just like the telephone you can't stop people using it.
"We can't say whether it has any impact on suicides.
"We do a lot of work with social networking sites and we are on these websites and hopefully people will come through to us."