Police in Northern Ireland were watching social media closely this week after Belfast teenagers reportedly used the Internet to organize a 100-person street fight. At least two boys were arrested during the weekend brawl, which was planned on Facebook, Instagram and Twitter and wasn't the first of its kind. Belfast Policing District superintendent Bobby Singleton told the News Letter that similar public clashes between teens have been happening for a year.

"The outworkings of them -- the violence on the streets -- is something we are greatly concern[ed] about," Singleton said. "So we are appealing to the parents -- do you know where your children are? And we are asking them to be more intrusive and find out where they are traveling to."

Police think the answer might be online. Earlier this month, local youth used social media to plan an illegal rave in Cavehill Country Park. More than 300 teenagers showed up after 10 p.m., most of them "heavily intoxicated" and "not knowing where they are and how to get home," according to a post on the Police Service of Northern Ireland's Facebook page.

Last Friday night, groups of teens appeared to be preparing to attack each other in the Royal Avenue area, BBC News reported. Police broke up the crowd once it started moving. Two girls, ages 14 and 15, were cautioned for disorderly behavior but not arrested.

Saturday's conflict attracted more young people. Authorities responded at about 10:30 p.m. when about 100 teens started gathering to fight in Belfast's main shopping area, according to the Belfast Telegraph. Two boys, ages 15 and 16, were arrested on charges of riotous behavior and criminal damage.

Singleton said that most of the fights, though worrisome, didn't appear to be political in nature. The teenagers were facing off over "things as simple as boyfriends and girlfriends falling out," he said.

Social media could be amplifying the conflicts among youth because the Internet allows them to connect with kids in other areas. For police, it could also hold the key to preventing future violence. "When large numbers of young people come together there is a safety risk," Singleton said. "We will continue to monitor social media and work with local communities to stay ahead of this."