Three West Midlands Ambulance Service staff in Shropshire have been suspended over information passed to the BBC.
The service said it was investigating a possible breach of the Data Protection Act after control room logs were shown to journalists at BBC Radio Shropshire.
It comes amid concerns over plans to close the ambulance control room in Shrewsbury and instead have two centres in Stafford and the Black Country.
Some staff believe that such a move would put lives at risk.
Control logs seen by BBC staff apparently showed ambulances were sent from Shropshire to help in Birmingham and the Black Country, reducing the number of emergency vehicles available in the county.
Ambulance bosses have written to the BBC asking reporters to reveal the source of the documents passed to the corporation.
The suspended members of staff have been told that if allegations against them prove to be true they would be guilty of gross misconduct.
In a statement, the service said: "West Midlands Ambulance Service can confirm that two members of staff have been suspended pending the outcome of an investigation into a possible breach of the Data Protection Act.
"The trust has acted to ensure patient confidentiality is maintained.
"Until the investigation is complete it would inappropriate to comment further."