Around 259 bhori of gold jewellery was stolen from two jewellery shops at Shah Ali Shopping Complex in Mirpur, Dhaka, in the early hours of Sunday.
Police suspect the theft was carried out with the involvement of five market security guards, who have been missing since the incident.
According to Darus Salam police, the theft took place sometime between Saturday night and early Sunday.
The stolen jewellery belonged to Al Razzak Jewellers, owned by Jasim Uddin, and A Hossain Jewellers, owned by Abul Hossain, both located on the second floor of the shopping complex.
Darus Salam Police Station Officer-in-Charge (OC) Dulal Hossain said preliminary findings suggest that around 200 bhori of gold ornaments were stolen from Al Razzak Jewellers and about 59 bhori from A Hossain Jewellers.
Describing it as a "well-planned theft," the OC said initial investigations indicate that the market's security guards were involved, along with three or four accomplices.
He said the guards had joined the market only a few days earlier with the intention of carrying out the theft.
Police also found that the national identity cards submitted by the guards during recruitment were fake, while their mobile phones have since been switched off.
The OC said police had obtained photographs of the suspects and were trying to identify them further by reviewing CCTV footage from the market.
According to investigators, security arrangements included both the market's own guards and a security guard assigned by the jewellery shops.
Police said the shop security guard was apparently rendered unconscious after being given sweets laced with a sedative.
CCTV footage also showed the market security guards allegedly taking part in the theft.
A case has been filed with Darus Salam Police Station. No arrests had been made as of 1am on Sunday.