Metro Manila (CNN Philippines) — In three weeks' time, the camp of Sen. Bongbong Marcos will file an election protest over what they called "massive rigging and manipulation of votes" in the May 9 polls.

This was bared on Tuesday by Jose Amor Amorado, head of Marcos' legal team and Abakada Party-list Rep. Jonathan Dela Cruz, the senator's political adviser. They intend to make the filing on June 28, a day before the deadline.

Amorado and Dela Cruz told reporters that there was a "secret fourth server" used during the elections — "which had been kept secret from the public by the Commission on Elections and Smartmatic," a press release from the Marcos camp said.

He explained that based on their findings, election results were transmitted to this fourth or "queue server" instead of being transmitted directly to the Municipal Board of Canvassers, the Comelec and the transparency server.

Related: Comelec, PPCRV, Smartmatic, face electoral sabotage charges

Dela Cruz said that this additional server was not divulged to the public and was never subjected to a source code review as what was done with the other servers.

Amorado added that there were also no watchers allowed to oversee the extra server.

"The truth has to come out one way or another," Amorado said earlier in the day after a preliminary investigation of the complaint for the violation of the cyber crime law, which they had previously filed against Comelec and Smartmatic personnel before the Manila City Prosecutor's Office.

Related: Marcos 'seriously considering' filing electoral protest

Over a week before, Marcos lawyer George Garcia had said the senator had been seriously mulling on filing an electoral protest — but it would cost somewhere between P30 million and P50 million to do so.

'Suspicious' change of script

Amorado said the protest would seek a recount of the votes in some areas — including the setting aside of the election results in areas where they said there were clear indications of fraud.

Marcos' camp said that the results of their initial findings indicated that between 9 p.m. and 10 p.m. of election day, results showed that the senator lost in 1,689 precincts.

Related: Marcos camp: New programming script introduced into Comelec’s transparency server

They said many of these precincts were from areas considered bailiwicks of Marcos — Leyte, Samar, Pangasinan and other areas in Region II.

As they claimed in their criminal complaint, the downtrend in the Marcos' votes began late evening of election day — after a change in the hash code or script of the system was made by Smartmatic's Marlon Garcia without seeking first the permission of the poll body.

Dela Cruz said that they owed it to those who voted for Marcos and to the entire Filipino people to find out what really happened in the 2016 elections.

Related: Comelec, Smartmatic on software alteration: Cosmetic change, no effect on results

Comelec had previously said several times that the script change had just been "cosmetic" and had not affected the election results.

Related: Marcos supporters to Comelec: Explain so-called 'cosmetic change'

Meanwhile, during the preliminary investigation, Smartmatic asked for ten more days to file their answer to the complaint.

Amorado added that if found guilty, respondents faced possible imprisonment of 6 to 12 years.

CNN Philippines' Anna Estanislao contributed to this report.