The Gateway International Bridge was forced to shut down for three hours Monday after a large group of undocumented migrants attempted to run across the bridge.

Video footage showed people running through traffic on Mexico's side with bags in hand.

Federal authorities say the people rushing the bridge did not have proper documents to enter the country. It is unclear the exact number of people that were involved.

Customs and Border Protection said the decision to shut down the bridge was a result of those large crowds.