Leslie Ross, 66, of Dromore was arrested last year after Michelle Bickerstaff, 47, died in April but was released unconditionally, the Belfast Telegraph reported. This time, the arrest also involved the deaths of Margaret Weise, 50, in August 2007 and Lily McKee, 52, in December 2002.
The Telegraph said police detained Ross on Tuesday after reviewing available evidence on Weise's and McKee's deaths.
McKee's daughter, Jenny Dickson, said her mother, who was divorced, had an 11-year relationship with Ross.
"I know that the police have been working hard with these cases, and I am not prepared to give any details as I would not want to jeopardize their inquiry and we want to see justice," she said.
Officers from the serious crime branch of the Police Service of Northern Ireland were also believed to be questioning Ross about
possible crimes involving other women.