Dozens were left injured after a tractor-trailer carrying stones and gravel overturned and lost its load early Monday in Montgomery County, Maryland, Texas, leading to a multi-vehicle collision involving at least 20 vehicles. Montgomery County police and fire personnel have been responding to the massive crash on I-270.

The crash was reported to have occurred in the southbound lanes of Interstate 270 just after Middlebrook Roa and 20 vehicles were involved. Officials said the trailer carrying stones and gravel overturned after colliding with another vehicle, losing its load and causing drivers behind it to crash.

All lanes of Interstate 270 were closed as of 5:30 a.m. EDT. Traffic is being detoured onto Route 355. Police have asked drivers to avoid the area of the crash.

No specific injuries were reported, however, emergency personnel are responding to the crash as a "mass casualty incident."

The spokesman for the Montgomery County Fire Department stated that at least two dozen patients are being evaluated currently; some had already been transported to hospitals, including "several traumas" so far. 

Dump Truck In this representational photo, a dump truck carrying boulders makes its way onto the Oroville Dam as workers try to fix the damage below the emergency spillway at Oroville Lake in California, Feb. 13, 2017. Photo: Getty Images/ Elijah Nouvelage

Videos and photos posted on social media showed the scene of the crash.