THE man being questioned by gardai about his mother's death was released early from a psychiatric unit this summer, sources claim.
It is understood that Paul Henry (25) had previously served time in Loughlin House and Castlerea Prison for motoring offences.
And it is believed that he was placed in a psychiatric unit in Roscommon in the summer but was released after three weeks, despite request by family members that he continue receiving care.
Ms Henry (47) was repeatedly knifed in a brutal attack at her house in Roscommon.
The mother-of-two had worked as an accounts clerk for a local chemist and had returned to study at Athlone Institute of Technology last Tuesday.
Her son Paul is in custody at Roscommon Garda Station and detectives are not seeking anyone else in connection with her violent death.
He is expected to be charged in connection with her death later today.
The tragedy unfolded on Saturday afternoon around 2.30pm and it has emerged that neighbours tried to fend off the attack.
Ms Henry, who was separated from her husband Phelim Henry, travelled from her home in Athlone to the house she had previously been renting at the Spinney, close to the landmark Abbey Hotel in Roscommon town.
Locals said Ms Henry had vacated the detached house some time ago and had returned to spend the afternoon cleaning it, before handing the property back to the landlord.
A local man who was parking his car in the immediate vicinity, spotted the trouble and went to her aid when he saw her in a distressed state, just outside her front door.
The man confronted her attacker, who initially ran off, before returning with a brush in an attempt at a second attack. He was again fended off, as another passer-by arrived to lend assistance.
An ambulance and gardai were on the scene shortly afterwards and a desperate attempt began to save Ms Henry's life.
A local doctor arrived and, along with paramedics, worked on Ms Henry as she lay on the roadside.
She was moved inside the ambulance, but after more than an hour of emergency treatment she died.
It is believed that concerns had been raised in recent weeks about her son Paul's behaviour and the family had sought help to have him placed in psychiatric care as recently as the week before last.
Friends said that Paul's behaviour had been "erratic" and that his family had wanted him placed in care but that would have needed an application made in court.
A post-mortem examination was carried out on Ms Henry's body yesterday.