Security is set to be tightened at a Birmingham hospital where an injured British soldier was allegedly threatened by a Muslim visitor.

Health chiefs have spent more than £7,000 on the new swipe card system at Selly Oak Hospital in a bid to protect British soldiers who are treated at the hospital on mixed wards with civilians.

The increased security was announced by Defence Minister Derek Twigg yesterday as he became the latest high profile figure to visit the hospital in recent weeks.

Asked about reports that an injured paratrooper at Selly Oak had recently been threatened by a Muslim visitor, Mr Twigg said he said he could find no evidence the incident happened. "When I heard about that, I was very concerned. I've looked into it and I can find no foundation for that happening. I can find no evidence it occurred," he said.

However, he added: "We want to look at security and make sure we provide an enhancement to that. We've listened to issues and concerns raised."

In the past week both the Prince of Wales and Defence Secretary Des Browne, as well as several senior military officers, have visited injured troops at the hospital - the Royal Centre for Defence Medicine's (RCDM) base in the Midlands.

Mr Twigg said he wanted to highlight a new operational welfare package announced yesterday for servicemen and women, as well as to hear first-hand about the medical treatment they were receiving.

His visit followed criticism of the Government over the conditions and medical treatment for troops fighting in Afghanistan and Iraq, with complaints about the lack of dedicated military hospital facilities in Britain.

The new swipe card system will be connected to CCTV cameras, which will be monitored by nursing staff to identify visitors before they are allowed on to the wards.

Mr Twigg, who replaced West Bromwich MP Tom Watson after he quit his post in a bid to force the Prime Minister to stand down last month, stressed these measures had been agreed months before his visit.

He said: "As a new minister, I wanted to come as soon as possible to visit injured service personnel and hear what they had to say about their treatment.

"I've been very, very impressed by the hospital and the way they are working together, military and civilian, and it's clear they are getting really good treatment."

The minister was also given a tour of the Alexandra Wing where military outpatients and their families are looked after.

A Ministry of Defence spokeswoman confirmed the RCDM were in talks about introducing "military managed wards" but added armed forces personnel would still be treated alongside civilian patients.

She said: "At the moment civilian nurses manage the wards with assistance from military and civilian doctors and nurses, but we're looking to have more military personnel on wards occupied by young soldiers.

"These would still be mixed wards, they wouldn't work otherwise. Where soldiers are sent depends on their needs, so if they come in with a brain injury they would go to a neurological ward rather than a military managed one, because that's where the expertise is."

Wing Commander Ian Sargeant, a consultant trauma and orthopaedic surgeon at Selly Oak, added: "If this incident did happen on the ward, then we're very distressed by it, but as far as we're concerned it didn't happen."

Tim Jones, University Hospital Birmingham NHS Foundation Trust's acting chief operating officer, said the system should be operational by the end of next week.

He added: "We know this system works and I am confident it will be a success on these wards."