Thousands of rail passengers have faced delays and cancellations after suspected saboteurs disrupted train services in the Netherlands during Tuesday morning's rush hour.
Pipes were attached to rails at 24 locations across central and northern Netherlands, the rail operator said.
The busiest western regions of the country were also affected by the major outage.
"Materials deliberately placed on the tracks have been found at several locations. This is causing track-circuit failures. It appears to be a case of sabotage," ProRail said in a statement.
Joke van der Cruysen, spokesperson for the company, added: "It appears that this material was deliberately placed on the tracks.
"The police are currently involved and are actively investigating the cause and the reasons behind this."
There was no immediate indication of who was suspected of being behind it.
ProRail said it was working to clear all rails and handling material taken off rails carefully so as not to compromise potential evidence, Ms van der Cruysen said, adding the company will try to restore sevices "as soon as possible".
Police spokeswoman Marloes Wesselink confirmed that an investigation was underway, but declined to give further details. She said that she wasn't aware of any claim of responsibility.
National railway company NS said that train services around the central cities of Zwolle, Deventer and Amersfoort were hit hard around the morning rush hour, telling passengers "it is not yet clear how long it will take for train services to return to normal."
Footage of long, thin pipes being removed from the tracks was shown by Dutch broadcaster NOS.
At Steenwijk, near the country's northwest coast, "a train struck the rolling stock, but this had no consequences for the train", according to ProRail.
The disruption had "major consequences for train traffic in the central and northern Netherlands," it said, warning travellers "should expect delays, cancelled trains, and extra travel time.
"Several level crossings are also malfunctioning, which could affect road traffic."
There were no reports of any injuries.
Road traffic suffered a knock-on effect as several level crossings were closed, ProRail said.
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It was unable to say when services might return to normal and advised passengers to get up-to-date travel information before departure.
In an update posted at 11.36am, local time, NOS said P parts of the track had reopened, but the operator warned "no trains are running yet on the Zwolle-Amersfoort, Amersfoort-Deventer, and Deventer-Almelo routes. It is unclear how long this will last".
Material has been found on the tracks in at least eight locations, NOS said.
It added that there is footage of "pipes being removed near Veenendaal and Olst".
(c) Sky News 2026: Suspected sabotage to trains during Dutch rush hour after pipes left on track
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