LONDON (Reuters) - British newspaper publisher Trinity Mirror
"The Group does not accept wrong doing within its business and takes these allegations seriously," the company said in a statement.
The practice of phone hacking to obtain illegally material for stories came to light two year ago at Rupert Murdoch's News Corp's
Police arrested four former editors from the Sunday Mirror tabloid in March - the first arrests related to a title outside Murdoch's stable - and said they were looking into a suspected conspiracy at Mirror Group between 2003 and 2004 to hack into voicemails.
Shares in the group, which plunged to a four-month low of 81.5 pence in March following the arrests before gradually recovering, were down 6.6 percent at 119.75 pence at 0707 GMT (2:07 EDT).
A source familiar with the matter told Reuters in August that London police were also actively investigating Murdoch's British newspaper business for possible criminal violations over allegations of phone-hacking and illegal payments to public officials by its journalists.
News Corp has said it is aware of the police inquiry but has given no further details.
The investigation had previously appeared to be focused on newspaper employees rather than the corporations.
(Reporting by Paul Sandle; editing by Kate Holton and Belinda Goldsmith)