Rupert Murdoch's News Corp. shares dropped Wednesday as investigations continue into one of its British newspapers alleged hacking into the voicemail belonging to a murdered teenager.

News Corp. shares dropped about  4 percent during afternoon trading, but the overall stock market picked up, CNNMoney reported.

The article from CNNMoney states that the phone-hacking scandal has resulted in a loss of advertising revenue as some big names in the car manufacturing industry, Ford and Renault, have said they won't advertise with the newspaper.

Additionally, some consumer product makers such as Procter & Gamble is said to be reviewing its options, according to the CNNMoney article.

As of March 31, News Corp., a global media company, had total assets approximately $60 billion and total annual revenues of approximately $33 billion, according to its website.

The drop in News Corp. shares came on the heels of allegations that journalists from the British Tabloid News of the World are being investigated on suspicion of allegedly hacked into a missing teen's voicemail. That teen was later found murdered.

It is also alleged that the newspaper is also involved in hacking into the phones belonging to celebrities, politicians and the father of a victim killed in the London bombings on July 7, 2005, CNNMoney reported.

British Prime Minister David Cameron has supported calls for public inquiries into reporting practices of the journalists at News of the World, and why a previous police investigation didn't reveal the allegations now surfacing, according to the Los Angeles Times.

Murdoch, who is the chairman of News Corp., issued a statement Wednesday calling the allegations deplorable and unacceptable. He said the company must fully and proactively cooperate with police investigation.

Murdoch also said his executive Rebekah Brooks, a former editor at News of the World, will continue her leadership despite allegations of phone hacking and police payments.

We are committed to addressing these issues fully and have taken a number of important steps to prevent them from happening again, Murdoch stated in the press release.

Murdoch has appointed Joel Klein, to provide oversight and guidance, and Viet Dinh, an independent director, will work with Klein to keep the News Corp.'s Board fully advised.