However, Lokwiya Pido, 31, a former treason suspect, said he did not know how Bongomin was killed.
Pido told the High Court in Kampala on Friday that he was the secretary of a meeting that discussed plans to kill Bongomin.
The MPs, Ronald Reagan Okumu (Aswa county) and Michael Nyeko Ocula (Kilak county) were indicted together with Steven Otim Olanya, Walter Ochan Raryang and David Oceng Pencho for the murder of Bongomin in 2002.
Pido said Okumu told the meeting that the murder was to sanctify the Acholi society of evil deeds like those that happened in 2000 and to rid Acholiland of leaders who are inciting the Government against the rebels.
He said he participated in coordinating the activities by disbursing funds to the youth, who were required to monitor Bongominâ€™s movements.
Pido said on February 8, 2002, Ocula told him they were required to go to Pabo to conclude their mission.
He said their meeting was held in Okumuâ€™s house with about 10 people, among them Ocula, Alex Otim, who was not in court, Olanya, Tonny Kitara, Peter Oloya and others.
Pido told court that Ocula gave him sh300,000 to give out to the youth to facilitate them in their assignments.
Ocula also gave sh100,000 to Olanya and about sh100,000 to Kitara. Kitara was the first state witness in this case.
Pido said they used a vehicle belonging to Gulu Municipality MP Norbert Mao to travel to Atiak and Pabo from where they would meet other youth.
Witness confesses attending murder plot