The dumping of a mountain bike on a railway line that hit a train and delayed services has been described as "stupid and extremely dangerous".

It was thrown on to the track between Milliken Park and Johnstone stations in Renfrewshire at about 6.20pm on Tuesday, British Transport Police said.

No-one was injured in the incident and police are checking CCTV to trace those responsible.

The train was damaged by hitting the black bike and services to Ayrshire from Glasgow Central station were disrupted while the track was cleared.

British Transport Police are appealing for witnesses.

Detective Constable Jim Duncan said: "We believe the bicycle was thrown onto the line deliberately and it is vitally important that we identify those responsible.

"No-one was injured but that does not change the fact that throwing anything onto the train tracks is not only stupid, but extremely dangerous.

"Officers carried out a widespread search of the area but did not find the culprits. The bicycle has been seized for forensic examination and officers are conducting house-to-house enquiries and looking at CCTV opportunities to identify those responsible.

"If you know who was responsible, or have any information that could assist our investigation, we want to hear from you."

Anyone with information is asked to contact BTP officials on 0800 40 50 40 quoting reference 411 of 19/11/13 or Crimestoppers anonymously on 0800 555 111.