More than 20 vehicles were involved in a crash on Interstate 270 in Maryland Monday morning after a tractor trailer carrying stones and gravel lost its load along the busy roadway. 

The tractor trailer was traveling along I-270 southbound when it lost its load. The vehicles behind the tractor trailer were not able to avoid the stone and gravel. 

All southbound lanes of I-270 are closed at this time. 

Two dozen people are being evaluated, fire officials say. A few people have been taken to the hospital with injuries.