A group of men from Maharashtra and Karnataka has allegedly robbed several jewellery stores in central and south Calcutta posing as CBI officers, police said on Friday.

The police said six persons have been arrested, three in Maharashtra and Karnataka each. They had put up in a rented accommodation in Howrah’s Bauria and were members of what the police said was an “Iranigang”.

“Three members are from the Bidar district of Karnataka and the rest from the Jalgaon district of Maharashtra. Barring one, all of them are in their mid-30s and early 40s,” said a senior police officer.

“They are members of the Irani gang and allegedly robbed gold ornaments in Burrabazar, Bowbazar, Muchipara and Gairahat. Gang members would intercept persons carrying jewellery from manufacturing units to showrooms posing as CBI officers and then disappear with the jewellery.”

Some of the crimes were committed on thoroughfares. Members would also enter jewellery shops identifying themselves as CBI officers and leave with gold items on the pretext of checking whether the gold was hallmarked or not, the officer said.

Three criminal cases were drawn up following complaints — two at Muchipara police station in August and one at Gariahat police station on November 11.

The detective department of the city police took over the investigation and realised that a gang from another state was involved in the robberies.

CCTV footage and information were shared with the police of other states, including Madhya Pradesh, Karnataka and Maharashtra. “It subsequently emerged that the gang was active in several other states,” the police said.

The modus operandi was the same and so was the target. After committing a few crimes, the gang would shift to another state, the police said.

A few days back, officers received a tip-off that members of the gang had reached Howrah and rented an accommodation in Bauria.

A raid by officers from the Howrah Rural District Police and their counterparts from the detective department of Kolkata Police was carried out late on Thursday and the accused were arrested early on Friday.