Ramna police arrested them early today in connection with the murders, UNB adds.
On secret information, a team of police conducted a raid in Ramna area and arrested them, said Deputy Commissioner (media) of Dhaka Metropolitan Police (DMP) Masudur Rahman.
The arrestees are FIR (First Information Report)-named accused in the sensational killing case, he said.
Unidentified assailants gunned down three people, including a woman, and injured another in a house following rivalry with the local land grabbers and extortionists at Sonalibagh in Moghbazar Thursday night.
The deceased were identified as Ranu Akhter Brishti, 28, Munna, 20, and Billal Hossain, 25.
The arrests were made after Brishti’s brother Kalachand filed a case against 15 people including Kailla Babu with Ramna Police Station on Friday night.
Police sources said there had long been an intense rivalry among three alleged local land grabbers and extortionists --Kailla Babu, Kalachand (Brishti’s elder bother) and Rony.