Six people were killed and 16 others injured early Wednesday when a Danish passenger train apparently hit falling cargo from a passing freight train as it crossed a bridge linking central Denmark's islands.

The rail operator, Danish Railways, earlier told Denmark's TV2 that the victims were passengers on a train going from the city of Odense, on the central Danish island of Fyn, to Copenhagen when the accident took place about 8 a.m. local time.

Police spokesman Lars Braemhoej said that while "we do not know precisely what caused the accident," one possible cause was that cargo from a passing freight train fell off and hit the passenger train. He added there was "considerable damage" on the passenger train.

Police declined to comment on a report from Denmark's TV2 channel that a container had likely fallen off the cargo train.

Danish media initially reported that a tarpaulin on a freight train hit the passenger train, which was going in the opposite direction, prompting it to brake violently.

"Ordinary Danes on their way to work or heading home from the Christmas holidays have had their lives smashed," said Prime Minister Lars Loekke Rasmussen.

Photos from the scene show the freight train was carrying crates of beer, and the tarpaulin that covered the train was torn in pieces.

Kasper Elbjoern, spokesman for Danish brewery group Carlsberg, confirmed that a freight train transporting its cargo was involved in the accident.

Police said those hurt sustained light to moderate injuries.

Jesper Nielsen, who was on the passenger train, told Denmark's TV2 the train "was out on the bridge when there was a huge 'bang' .... very quickly thereafter, the train braked."

The accident took place on a road-and-rail bridge, part of the Storebaelt system of bridges and a tunnel linking the Danish islands of Zealand and Funen.

Flemming Jensen, the CEO of state-owned Danish Railways, said police and the Danish Accident Investigation Board are investigating the damages. He said the operator "will contribute everything that we can to the investigations."

In a statement, police urged passengers to contact next of kin to inform them of their safety and urged people not to share photos and videos of the accident.

The government agency responsible for Danish railways, said on Twitter no trains would cross the Storebaelt link Wednesday, adding it was aiming to allow crossings Thursday.

The transport system was closed to cars overnight because of strong winds but trains could pass. Road traffic resumed Wednesday with a 50 kph (31 mph) speed limit.