Police in South Africa's capital, Pretoria, claim to have to caught the "dumbest criminal" this year.
The man claimed he had been held up at gunpoint
The man walked into a station to report that he had been held up at gunpoint by a gang who had stolen his mobile phone.
But when the detective phoned the number of the phone reportedly stolen, it rang in the complainant's pocket.
"The shock left him speechless for a few minutes," said police spokesman Eugene Opperman, adding that the man, 25, was then arrested for perjury.
The police issued a statement entitled "Dumbest criminal?" with details of the weekend incident, South Africa's Star newspaper reports.
"At the end of the interview, he rang the complainant's cell phone number, and it rang in the man's pocket," Mr Opperman said, according to the Beeld paper.
"He told the detective that he'd given him the wrong number," he said.
"But couldn't explain why the phone in his pocket had the corresponding serial number, or why it was same make and fitted the description he had given of the 'stolen phone'."
South Africa's reputation has long been tarnished by the high levels of crime, often accompanied by extreme violence involving guns.