NORTHSHORE -- I-55 southbound reopened near Manchac after an accident involving a prison transport bus carrying prisoners to Orleans Parish Prison closed the highway for hours.

The highway reopened around 8:30 a.m. after closing around 7 a.m., causing traffic to back up for miles.

Traffic was being diverted to US 51. 

State Police Trooper Dustin Dwight, Troop L, said the accident involved three vehicles including an Orleans Parish prison bus carrying prisoners.

Dwight said the bus was carrying a total of 16 people. The number of people in the other two vehicles was not immediately available. 

Dwight said there were no serious injuries, but some passengers on the prison bus were injured and transported to a hospital. Dwight said he was not sure the number of people injured.

The cause of the crash remains under investigation.

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