The man who knifed to death two police officials had a "hit list" of VIPs, police and rappers, the Paris prosecutor said Tuesday.

The killer, 25-year-old Larossi Abballa, had pledged allegiance to the Islamic State group three weeks ago, Francois Molins told a news conference. 

Earlier on Tuesday, a police source said two people had been detained in connection with the attack, and Molins confirmed that a third person had also been taken into custody as part of the investigation into Monday's double murder.