A book reportedly written by a Canadian serial killer has been removed from Amazon's website within hours of being put on sale online.

Outskirts Press, which published the book, issued a statement Monday saying it had asked Amazon to remove the book from its website and apologizing to victims' families.

Robert Pickton was convicted in 2007 of six counts of second-degree murder in the deaths of sex workers. Pickton slaughtered the women at his pig farm and fed some remains to his pigs. He was sentenced to life in prison.

By Monday afternoon, the 144-page memoir titled "Pickton: In His Own Words" was no longer available from online retailer Amazon.

Canadian Public Safety Minister Ralph Goodale told Parliament the Correctional Service of Canada is investigating how the manuscript was smuggled out of prison.