Both vehicles have been damaged by the fire near the Army Stadium
Local police's Sub Inspector Based Mia said the incident occurred around 8am at Amin Bazar area.
He said the two victims have been identified as Shah Alam and 'Saidur.'
Quoting locals, Mia said the three got tangled with the overhead power cable while erecting a signpost for a dental clinic.
The three died on the spot, he added. "We have initially got names of two victims, but yet to get other details. All the three victims were between 25 and 28."
Police said the bodies have been sent to the morgue, but could not confirm whether anyone else had been injured.
Sub Inspector Mia said they were looking for the dental clinic's owner and staff.