Dolan twins opening night of 4OU tour halted after crush

Dolan BrothersGrayson Dolan / Instagram

Emergency services were called to the opening night of the Dolan twins' world tour.

The YouTubers kicked off their 4OU Tour in New Jersey by taking their shirts off resulting in fans pushing to the front and some even fainting.

It meant the show had to be stopped while medical assistance was given.

Ethan tweeted: For every beautiful fan out here at the show in NJ.. Please be seated and relax and breathe. We're all a fam. We want the show to go on

A fan uploaded what happened on Instagram.

Jersey Shore University Medical Center confirmed to Newsbeat they treated fans from the arena with one being sent to hospital.

Ethan and Grayson Dolan are 16 and have been YouTubers for the past two years.

They film pretty much everything about their lives and upload it online.

The brothers have amassed millions of followers on YouTube, Vine, Snapchat and Instagram.

iPlay America, where the concert was being held, posted a statement online about the event.

The arena posted on Facebook: This evening during the Dolan Twins concert at iPlay America, some guests crowded toward the stage which caused some of those who were closest to the stage to panic. Some complained of losing their breath. We alleviated the crowding asap, asking all guests to sit on the floor for the remainder of the concert. As a precaution, ambulances were called to the scene. There were no serious injuries.Facebook

Some have posted online that they saw people "crying" and "in pain".

The brothers tweeted after the show his thanks to fans.

Grayson posted: 4ou fans are THE BEST fans in the world. Can't tell you how grateful I am to have you all supporting us.

Ethan wrote: I never smile with my teeth, but I don't think I smiled withOUT my teeth at all tonight. You make me happy, thanks for that .

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