The group had named Senate President Bukola Saraki, Speaker Yakubu Dogara, Deputy Speaker Yusuf Lasun in the scandal.
Melaye, who is the Chairman, Senate Committee on FCT, allegedly stole the money from the Federal Capital Development Authority (FCDA).
According to a statement by the Citizens Action To Take Back Nigeria (CATMAN), a civil society group, some principal officers of the National Assembly were also involved in the theft.
The group named Senate President Bukola Saraki, Speaker Yakubu Dogara, Deputy Speaker Yusuf Lasun in the scandal.
The statement signed on Thursday, February 23, in Abuja by the co-convener of CATBAN Ibrahim Garba Wala, said the four principal officers "conspired to steal the said sum through false pretense under the guise of accommodation."
On February 3, 2017, CATBAN had in a detailed petition to the Inspector General of Police, and the EFCC demanded the arrest and subsequent prosecution of the lawmakers and their accomplices.
The group added that failure to arrest them would force it to assist in effecting the arrest accordingly.
The statement said: "Bearing in mind that CATBAN was effectively preparing for the next line of action on the issue being that the deadline extended to the security agencies had expired, we find the news of Senator Dino Malaye’s grill as a welcome development and we commend the EFCC for swiftly responding to our call, as we await the outcome of the interrogation and subsequent prosecution of the culprits.
"For the records, incriminating documents made available to the media revealed how Senator Dino Malaye fraudulently used his office as Chairman, Senate committee on FCT to initiate and execute the deal on behalf of the four (4) principal officers."