The court on Friday issued a detention order against a 50-year-old man identified as M.S., saying there were reasonable grounds to suspect that he had committed a war crime against the four-member family.
Towards the end of August this year, the police arrested four former members of the Croatian Army on suspicion of murdering Radomir (38) and Anica (39) Olujic and their children, Milena (16) and Marko (13) during the night between February 17 and 18, 1992.
M.S. was also arrested then, but was released after an interview with the police.
Police are still looking for a person known as "Bosanac" on suspicion of involvement in the murder.
The police said it was a murder for gain, while the County Prosecutor's Office described it as a war crime against civilians.