Earlier on Saturday, police produced them before the judge with a 7-day remand plea, said court inspector Chandan Kumar Chakrabarty.
Four suspects have so far been arrested in connection with murder of Rohingya leader Mohib Ullah at Lambashia camp-1 in Ukhiya.
Shawkat was arrested on Saturday afternoon from a Kutupalong Rohingya camp, said officer-in-charge of Ukhiya police station Sanjur Morshed.
Armed Police Battalion (APBn) personnel arrested Ziaur and Salam on Friday from Kutupalong camps and Selim on Friday noon from Kutupalong camp-6.
SP Naimul Haque, commander of the 14th APBn, said the three arrestees were later handed over to Ukhiya police station.
On Thursday night, police registered a murder case over Mohib Ullah’s murder following a complaint from Mohib Ullah’s brother Habib Ullah, said officer-in-charge Sanjur Morshed.
Unknown assailants gunned down Mohib on Wednesday night.
He was buried in Lambashia camp-1 in Ukhiya upazila on Thursday afternoon after his namaz-e-janaza, which was attended by a large number of Rohingya refugees from camps in Ukhiya and Teknaf upazilas.
Formerly a teacher in Myanmar, the slain activist was popularly known as Master Mohib Ullah among the Rohingya refugees. He was the head of Arakan Rohingya Society for Peace and Human Rights (ARSPH) at Kutupalong camp.