Parents launch #MissinginManchester Twitter campaign to find missing children

MANCHESTER -- Parents are trying to locate their missing teens with help from social media after a terror attack at an Ariana Grande concert in Manchester.

The Twitter hashtags "Missing in Manchester" and "Manchester Missing" are being used to track down loved ones.

Olivia Campbell, 15, is among the missing. She went the to concert last night with her best friend. Her friend was located at a hospital, but Olivia is still missing.

Nell Jones, a 14-year-old girl with crutches, is also reported to be missing.

Martyn Hett, 29, has not been located since tweeting at the concert, writing, "When you sneak out for a toilet break on the Macy Gray song and the entire arena had the same idea" #DangerousWomanTour.

U.K. group Little Mix joined in the efforts, asking for help locating two children.

People on the lookout for children should beware of fake images claiming to be other missing concert goers. Some have been sharing images that have nothing to do with the concert, just for the sake of gaining likes and shares.

ISIS has claimed responsible for the attack. Twenty-two children and adults died in the bombing, and dozens more are injured.