The kidnappers of BBC correspondent Alan Johnston have released a new
video of him in which he is wearing what he says is an explosives vest, according to a report on the BBC's website.
In the tape, Mr Johnston says his captors have said they will detonate the vest if force is used to try to free him.
It is the second video released since Mr Johnston was abducted from a Gaza street on 12 March.
The BBC renewed its appeal for Mr Johnston's immediate release.
"It is very distressing for Alan's family and colleagues to see him being threatened in this way," a BBC statement said.
"We ask those holding Alan to avoid him being harmed by releasing him immediately.
"We are keeping his family fully informed and offering them our continued support."
Mr Johnston's father, Graham, said: "My family and I are obviously most concerned and distressed at this latest development.
"Our thoughts, of course, are with Alan in his present predicament. We earnestly request his abductors to release Alan, unharmed in any way."
In the tape, posted on a website used by militants, Mr Johnston is seen wearing a device around his torso and attached to shoulder straps.
"The situation now is very serious. As you can see I have been dressed in what is an explosive belt, which the kidnappers say will be detonated if there was any attempt to storm this area," he says.
Click here to read the full report, posted on the BBC's website.Ãƒâ€šÃ‚Â