The Irish News claims on its front page that many of the death threats made to Quinn Industrial Holdings (QIH) directors were communicated face to face and then reported to police.
QIH director John McCartin tells the newspaper he was repeatedly threatened by people he later identified to gardai (Irish police).
A Garda spokesman said the force "does not comment on remarks made by third parties" and that Commissioner Drew Harris is happy with the progress of the investigation.
Two men, one in his 20s and another in his 40s, and a woman in her 50s are in custody after searches in counties Cavan, Longford and Dublin.
The Daily Mirror reports on its front page that a "secret phone stash" of Cyril McGuinness, 54, who was a suspect in the investigation, has helped police.
Investigators said they have yet to establish the cause of his death, despite a post mortem examination that was carried out on Monday.
The Independent Office for Police Conduct said there was "no evidence" a Taser was used, but added that "work is still ongoing to confirm this".
Elsewhere, the Belfast Telegraph's front page features a report by Childline that says there has been a big increase in the number of children from Northern Ireland who have used the charity's counselling sessions after being "groomed and sexually exploited".
Childline's annual report reveals it carried out 140 counselling sessions concerning child sexual exploitation in NI in the past year, up 44% on the previous year.
According to the News Letter's front page, an attempt to smuggle 600 kilos of class C drugs into Belfast led to the unravelling of a huge anabolic steroid distribution network.
The National Crime Agency investigation began in 2014, after a seizure of the drugs at Heathrow Airport which were destined for a Belfast address.
Danish national Jacob Sporon-Fiedler ran an Indian pharmaceutical company that supplied four tonnes of anabolic steroids per month to Europe.
His gang in the UK included former bodybuilding champion Nathan Selcon who had a £1m home in Milton Keynes.
Sporon-Fiedler and Selcon admitted conspiring to import steroids at the Old Bailey.
On Thursday, Sporon-Fiedler, 38, was jailed for five years and four months. Selcon, 45, was also found guilty of conspiring to manufacture steroids and was sentenced to six years in prison.
Three other men were also convicted for their roles.
The Belfast Telegraph, Irish News and News Letter all feature a survey by the Royal College of GPs in Northern Ireland, which suggests just over a quarter of GPs (26%) in NI believe they will not be working in general practice in five years.
A third of those surveyed felt so stressed at least once a week that they could not cope.
On the back of the survey, west Belfast GP Dr George O'Neill told the Belfast Telegraph that "being a GP is a very worthwhile job, but full time, it's soul destroying".