A company suspected of making more than 200m illegal nuisance calls could have put lives at risk, a watchdog has found.

The unnamed firm clogged up a safety line for pedestrians and drivers at unmanned level crossings.

The Information Commissioner's Office (ICO) searched the premises in Clydebank, West Dunbartonshire, following complaints about automated nuisance calls promoting boiler and window replacement schemes.

The ICO said some of the calls were made to Network Rail's Banavie control centre, near Fort William in the Highlands, used by people to check it is safe to use unmanned rail crossings.

The calls, which contain recorded messages, often aligned themselves to non-existent Scottish and UK Government initiatives.

Computer equipment and documents were seized from the business as part of the ICO investigation.

The watchdog said the 200m-plus calls the firm is suspected of making is one of the highest it has ever investigated.

The body has the power to issue fines of up to £500,000 for law breaches around automated marketing calls.

Ken Macdonald, head of ICO Scotland, said: "These calls have caused millions of people disruption, annoyance and distress, but not only this, those made to a control centre charged with public safety may have endangered lives.

"Companies behind nuisance calls should know that people are sick of them, and when people complain to us, we will act."