"We take any allegations extremely seriously and have launched an urgent investigation.
The matters leading to the allegations appear to have arisen earlier this year when the undercover reporter participated in training.
"All issues relating to staff conduct are extremely important to us, particularly in relation to patient safety.
We strictly enforce our policies for managing staff conduct at all times including whenever we receive reports of inappropriate conduct or behaviour.
"We are working closely with the NHS clinical commissioning groups to ensure that any concerns are thoroughly investigated and we have appointed a senior investigating officer to oversee this process.
"The Sun did not share their evidence prior to publication and we will be asking them to disclose this to us to assist our investigation.
"As an NHS service provider we are committed to delivering high-quality services.