Police in California have seized computers belonging to the editor of a gadget blog which was involved in the purchase of an iPhone prototype.
Gizmodo had admitted it paid $5,000 to an unnamed individual for the next generation device, which was reportedly left in a bar by an Apple employee.
Editor Jason Chen published photographs and videos of the phone last week.
Gizmodo may have violated a California law covering the appropriation of stolen property for personal benefit.
The phone was lost by 27-year-old Apple software engineer Gray Powell.
Mr Chen told newswire AFP that he and his wife returned from having dinner on Friday night to find police searching their home.
"The officers had a computer and were cataloguing all the items they took from my house. They told me they were here for a few hours already and had to break the front door open because I wasn't at home," he said.
The technology blog published the search warrant documents online and said they state that the computer and other devices may have been used to commit a felony.
Apple wrote to Gizmodo last week asking it to return the prototype handset, which it complied with.
The technology blog had already published details of the next-generation iPhone, which is expected to be unveiled later this year.
According to Gizmodo, new features include a front-facing video camera and an improved camera with larger lens and a flash. It is also thinner and has improved battery life.
Critics argue that Gizmodo has committed a crime because it knowingly handled stolen goods and point out that there are clear laws about what to do with found property.
Gizmodo is owned by Gawker Media and its chief operating officer, Gaby Darbyshire, said it expected the immediate return of Mr Chen's computers and servers.
"Under both state and federal law, a search warrant may not be validly issued to confiscate the property of a journalist," she wrote in a letter to San Mateo County authorities on Saturday.
"It is abundantly clear under the law that a search warrant to remove these items was invalid. The appropriate method of obtaining such materials would be the issuance of a subpoena," said Ms. Darbyshire.
Gawker Media said the issue now throws into question whether or not bloggers are considered journalists under the law.
Advocacy group the Electronic Frontier Foundation (EFF), which is following the case, said it found the latest events worrying for two reasons.
"You have a reporter who is disseminating newsworthy information to the public that are supposed to be protected from search and seizures. These protections apply to people who collect information in order to report it to the public regardless of what name you slap on them; blogger, journalist or whatever," Jennifer Ganick, the EFFs civil liberties director told BBC News.
The second issue the EFF is concerned about is if police officers are doing the investigative work of a private company.
"If there was some offence here it is not apparent what it is", she said.
The raids were conducted by the Rapid Enforcement Allied Computer Team (React), a Californian computer crime taskforce.
The taskforce was set up on 1997 to address the rising problem of computer fraud and identity theft.
It works closely with the computer industry and Apple is reported to be one of 25 tech firms to sit on the steering committee.