Games officials said race walker Irfan Kolothum Thodi and triple jumper Rakesh Babu were found to have a syringe in their room in the athletes' village on the Gold Coast.
Weightlifter Olivier Matam Matam and boxers Christian Ndzie Tsoye and Simplice Fotsala have been missing since earlier this week, while weightlifters Arcangeline Fouodji Sonkbou and Petit Minkoumba went missing on Tuesday.
"The testimony of the athletes. are both unreliable and evasive", Martin told reporters.
One who failed to appear was Ulrich Rodrigue Yombo who skipped Wednesday morning's weigh-in for his quarter-final bout in the 81kg division against Canada's Harley O'Reilly.
"These athletes, three weightlifters and five boxers, were part of the team that had a training camp in Warwick before getting to Gold Coast", said a press release from Team Cameroon.
The Cameroonian athletes could apply for asylum in Australia but they would risk a lengthy stay in detention if Border Force canceled their existing visas, Burnside said.
He said they were "taking the mickey".More news: A New BioShock Game Is Reportedly in the Works
African athletes committing vanishing acts at the Australian Commonwealth Games have increased to 13, with five more from Uganda and Rwanda also disappearing.
Nso said the rest of Team Cameroon - 34 in total, including basketballers and two other weightlifters - and their officials have already left Australia.
"We imagine they went away wilfully".
"The authorities are very disappointed with the deserters - some did not even compete".
He told news.com.au he "doesn't think they'll come back".
Before the Games began, the home affairs minister, Peter Dutton, warned that all athletes would be closely monitored to ensure they did not overstay their visas and returned home after competition ended.
"The safety and welfare of those athletes from the Team Cameroon perspective is being taken very, very seriously, but we are obviously monitoring that situation with Team Cameroon", Mr Grevemberg added.