Vacationers riding a new aerial gondola system at Walt Disney World in Florida on Saturday night were stranded in the air for several hours after a malfunction brought some of the gondolas to a halt.

The Disney Skyliner gondola system opened on Sept. 29. Three independently running sections carrying 300 gondolas in total connect Epcot, Disney’s Hollywood Studios and three Walt Disney World resorts, according to Disney World.

Passengers who were in the gondolas on Saturday said one of the sections came to an abrupt stop around 8 p.m. Pictures posted on social media showed several gondolas scrunched together at one of the system’s five stations in an apparent collision.

In a statement on Sunday evening, Disney World said a team was “diligently looking into the cause of last night’s malfunction.” In the meantime, the whole gondola system was shut down.