Justice Minister Kim Kyung-han released a statement saying the probe "will come to a close," the Korea Times reported.
"I cannot hold back the shock and sadness from Roh's unexpected death," the minister said.
Prosecutors investigating allegations that Roh received millions of dollars in bribes questioned the former president in April. His wife and son had also been questioned, and some of his relatives, including a brother, charged.
His wife was about to be questioned again, and Roh might have been indicted in the next few days, the Times said.
Roh jumped or fell on a mountainside near his home early Saturday morning.
Many of Roh's neighbors in Bongha Village blamed his successor, Lee Myung-bak, for the apparent suicide. Some also accused the news media of biased coverage of the investigation.