After the bus crash, a car also ploughed into the accident site in the Fürth district near Nuremberg in the southern state of Bavaria.
Three ambulance rescue helicopters and a police chopper were deployed along with scores of emergency services personnel.
Firefighters used metal-cutting equipment to free at least four people who were trapped in the crumpled wreckage of the vehicles.
Around 2 p.m. the two buses collided head-on. The car drove into the scene of the accident later. The state road 2245 between Ammerndorf and Weinzierlein near Fürth is currently completely closed, according to local news website nordbayern.de.
Many children are among the injured, according to police. They were sitting in the two buses because the lessons had ended shortly before. Yet the buses, as previously reported by other local media, are not school buses.
All the injured people are being cared for, police spokesman Bert Rauenbusch told nordbayern.de. He said that the cause of the accident has not yet been determined, adding that the first steps are to treat those injured.
It could take until later in the evening for the scene of the accident to be cleared, according to police.