A team of Rapid Action Battalion (RAB) arrested three persons, including a Special Branch’s (SB) Sub-Inspector (SI) of police, with an illegal gun in the city’s Uttara on Wednesday afternoon. The arrested SI identified as Md Asaduzzaman, has link to illegal gun trading, RAB officials claimed. A 9-mm gun and 13 rounds of bullets were seized from them, the RAB officials said.The two other arrested persons have been identified as Saiful Islam and Mahmudul Islam, he added. RAB-1 Commander Tuhin Mohammad Masud said that the trio were detained from an under-construction house at Uttara, Sector-6 around 4:30pm. RAB Additional Director General Colonel Ziaul Ahsan said that the arrest was the outcome of the RAB’s sting operation to catch illegal arms dealers.He said, “RAB officials in disguise had first proposed to buy arms from the gang. The arrest took place when the trade was taking place.” Legal measures were afoot against the SI and two others, he further said.