The Delhi Police Crime Branch will investigate the cases of violence at the Red Fort, ITO and seven other places during the farmers' tractor parade on Republic Day, an official said.
The official said the police have so far registered 33 FIRs in connection with the violence that left 394 police personnel injured and one protester dead on January 26.
Lookout notices have been issued against 44 people, the official said.
Thousands of protesting farmers had clashed with the police during the tractor rally called by farmer unions to highlight their demand for repeal of the Centre's three farm laws.
Many of the protesters, driving tractors, reached the Red Fort and entered the monument. Some protesters even hoisted religious flags on its domes and the flagstaff at the ramparts, where the national flag is unfurled by the prime minister on Independence Day.