Circle officer (city) Sangram Singh said the incident occurred in Kotwali police station area around 11.30 am.
The seriously injured occupants of the bio-medical waste vehicle were taken to a hospital where doctors declared them dead, police said.
The deceased have been identified as Dinesh Sharma (36), Ravnindra (35) and Monu (32), all residents of Ghaziabad, the circle officer added.
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