The BBC was today accused of wasting NHS time after a Panorama reporter was discovered working undercover in a Suffolk hospital.

Shabnam Grewal, who works for BBC1's Panorama, was sacked as a housekeeper at the West Suffolk hospital in Bury St Edmunds after staff became suspicious.

A hospital spokesman condemned the attempted investigation and accused the BBC of wasting "valuable NHS time and resources". It has launched an inquiry into how the reporter was given the job.

"We were suspicious before she joined us on account of the number and nature of the telephone inquiries she made, and these suspicions were compounded by her behaviour on Wednesday," he said.

"When challenged, she was unable to give a satisfactory response to our questions and was, therefore, suspended. Our understanding is that she was an undercover reporter."

The appointment has sparked fresh calls for better checks to be made on applicants to ensure the safety of patients, but the hospital said it had followed correct procedures.

"This woman has taken up valuable NHS time and resources and we totally condemn this type of behaviour," added the spokesman for the hospital.

A BBC spokesman said: "I can confirm a BBC employee working for Panorama was exploring a possible health story at West Suffolk hospital on Wednesday."

The corporation refused to reveal the focus of the planned investigation.

"We only ever place reporters undercover after scrupulous research and where there is clear public interest. At all times they adhere to the BBC's strict editorial guidelines."

Grewal was suspended from her job on Wednesday just hours after starting when staff became suspicious.

"She seemed surgically attached to her bag as if she had some kind of recording device in it, but when someone asked to look in it she said no and came over very cagey," said a source at the hospital.

"She also said that she had come up from London for the job, but couldn't remember the name of the village in Suffolk she was staying in. She was rumbled within hours."

The hospital said it had checked two of the woman's references before taking her on.

But neither the hospital nor the BBC would reveal details of what the reporter had written. Richard Spring, the MP for West Suffolk, described the incident as "curious" and urged the hospital to take greater care when checking references.

The bungled investigation came a month after the Sun's Brian Flynn failed in his attempt to go undercover as a Kosovan refugee seeking asylum in the UK. Flynn was rumbled after he was questioned by immigration officers at Dover, who discovered he was unable to speak either of the region's languages, Serbo-Croat or Albanian.

An undercover investigation by Channel 4's Dispatches programme in January asked alarming questions about the treatment of patients in British hospitals and the standards of cleanliness on wards.

One of the BBC's most successful undercover investigations of recent years was BBC1's The Secret Policeman in 2003, which exposed racism among trainee police officers.

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