COPENHAGEN, Denmark (AP) — Two trains collided in Denmark early Thursday, prompting a massive emergency response for what police called a major accident.

The collision occurred around 6:30 a.m. about 40 kilometers (25 miles) north of Copenhagen. It was not immediately clear how many people were injured.

Photos from the scene show the front ends of the trains smashed, though both remained upright on the tracks.

Other details were not available.