(CNN) -- More than 100 people were injured when two passenger trains collided in Amsterdam on Saturday, authorities said.
A national police spokesman put the number of people hurt at 136, while the spokesman for the Amsterdam mayor said 117 people had been injured. Of those hurt, dozens were severely injured and at least a dozen people were in critical condition, both spokesmen said.
"Everybody was in panic. Everybody was screaming. A lot of people were injured. There was a lot of blood," Giovanni Laisina, a passenger, told CNN.
Though his head was knocked hard against a window, he said he is fine.
"I was shocked in the beginning, but because I don't have any injures at all ... for me it's OK. It's a little bit surreal," said Laisina.
The trains collided between the Amsterdam Sloterdijk and the Amsterdam Centraal stations, CNN affiliate RTL reported, citing rescue officials. Video from the scene showed rescue personnel working around the two trains, as an injured person was wheeled away on a stretcher.
"My roommate and I heard the train signaling an emergency signal -- then we heard the intense impact of the collision," said Max Tau, whose apartment is about 20 yards from the tracks. "It rattled our windows, and there was a considerable amount of electrical and rock dust all around.
"The sound would be comparable to that of an electrical transformer blowing up. It was really intense," Tau said.
It was not immediately clear why the trains were on the same tracks, though Ed Kraszewski, the police spokesman, did not rule out that one of the trains might have ignored a red signal.
Amsterdam Mayor Eberhard van der Laan visited with some of the passengers after the accident and offered his condolences.
"There are many wounded, but luckily they got help quickly. All the attention and care go out to those people that are severely wounded. I hope that it will all end well," van der Laan said.
Journalist Eline Rietkerk contributed to this report for CNN.