Searches are continuing to try to identify the scene where Dublin dad Kenneth O'Brien was brutally murdered.
Gardai were concentrating on several sites alongside the Grand Canal near where his dismembered body was found in a suitcase.
The Herald can today reveal that a feared west Dublin criminal is also being probed over a possible link to the murder.
One theory being investigated is whether the victim had a brief fling with a woman known to the criminal.
However, this is just one line of enquiry in what is being called an "extremely complex case which keeps on throwing up new information".
Gardai are also investigating whether sinister threats were made to a woman known to Mr O'Brien (33) and other people known to him in the weeks before he was murdered.
"New pieces of information are coming in all the time and over 50 new lines of enquiry have opened up in the last 24 hours," a source said.
Dozens of gardai intensively searched farmhouses and land yesterday near where Mr O'Brien's body was found, but the scene of his murder has still not been identified.
Gardai denied reports that surfaced yesterday afternoon that a suspect had been arrested in the case.
They are appealing for anyone, "even courting couples", who may have been at the canal late on Friday night or early on Saturday morning when it is believed that Mr O'Brien's body was dumped.
Yesterday afternoon a number of Garda Water Unit divers searched lakes along the canal, while plain clothes units searched the building a few hundred metres away from where the victim was found.
Gardai will also launch a reconstruction of events at the Ardclough stretch of the canal this evening and tomorrow and intend to stop cars and walkers to find out if they had been in that area last weekend.
Gardai are also aware that other body parts could have been buried near the canal.
Detectives are understood to have searched a rented property and outhouses. One of the farm houses in question contains a vast amount of motorbikes and scrap metal.
Meanwhile, locals expressed their shock at the garda search.
One man said that it was "worrying" to think that the events that led to Mr O'Brien's death may have unfolded next to his property.
"It's truly awful, we're not being told much but hopefully it isn't the case that something as gruesome as this occurred here," the resident said.
"What happened to that poor man is absolutely shocking."
Yesterday gardai confirmed that they were investigating more than 200 lines of enquiry.