Irate residents have taken to the streets to express anger about the killing, which comes as the country reels from multiple shootings of unarmed citizens by police officers.
Mr Melaye was arrested at his residence in Abuja as a suspect in a homicide investigation.
The acting Inspector General of Police, Adamu Mohammed, has appointed a new spokesman for the Nigeria Police Force.
The entire drama began when the handing over event scheduled for 1:30 pm was shifted to 3pm.
From the strategies put in place by the former IGP, we will restrategise and make sure that we tackle these challenges squarely,” new IG said.
Police said a pump-action gun was recovered from Melaye’s house in July last year during a search of his property in Kogi State.
The officers forced the lawmaker, who was on the hospital bed, into an unmarked vehicle.
The lock down follows a directive by the leadership of the National Assembly.