The questions surrounding the way in which the San Francisco’s Police Department assisted the Apple security employees for a missing iPhone prototype believed to be iPhone 5, has triggered an internal investigation at the SFPD.

An earlier report said, four plain clothed police officers had accompanied two Apple security agents in the search of a San Francisco man’s home, from where the lost device was emanating signals. The policemen stood outside the house, while the two Apple representatives checked the suspect’s premise and his vehicle under the name of “official police work.”

Calederon, the suspect claimed to SF Weekly that the Apple employees never identifies themselves and the officers tried to intimidate and his family into cooperating with the search.

Ginny Walia of Ginny Walia Law Offices said, Police aren't supposed to try to obtain permission to search a home by putting someone under duress.

CNET had cited a source who said that it had been the SFPD officers who had asked Calderon if they could search his house and said that they would get a search warrant if he declined to let them in.

Calderon has no knowledge of where the lost device is, though he admitted that he was at the bar Cava 22, from where the iPhone went missing.

The whole story is similar to the loss of iPhone 4 prototype last year before the release of the device.

However, this time it is not even verified yet whether the lost phone is an iPhone 5 prototype or Apple was trying to retrieve some kind of arbitrary test unit which isn’t set to become a consumer product.