Two people remained in Garda custody on Monday evening following the discovery of a body in Co Wexford.
The body of a 27-year-old man was found at Carrigfoyle Lake, close to Wexford town, on Sunday.
It came as a missing person appeal for Stephen Ring was called off.
He was reported missing in Wexford town on October 15.
A post-mortem examination has been carried out on the body.
Gardai said the results were not being disclosed for operational reasons.
On Sunday, a man in his 40s and a woman in her 30s were arrested under Section Four of the Criminal Justice Act.
They remained in custody on Monday evening.
The area around the lake remained sealed off on Monday while investigations continued.
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