"Prosecution action is considered on a case-by-case basis, and no decision is likely until the suspensions are reviewed in the new year."
Breaches include students studying less than the minimum 20 hours per week, misleading or poorly maintained attendance records and fee discrepancies.
The four institutions have a combined total of 842 international students, but the suspensions will only affect new or undecided visa applications.
Meanwhile, the number of Chinese students with fraudulent visas who are unlawfully in the country has increased to 162, from 74 in July.
Fifty-two others - also part of a group of 300 whose applications contained fake qualifications and falsified bank statements, remain in the country but their permits have not yet expired.
Mr McGill said one immigration agent might be implicated in the fraud and the agency had shared this information with the Chinese authorities. He would not disclose details about the agent.
"The issue of visas obtained fraudulently was confined to our Beijing office and locally employed staff," Mr McGill said.
"The investigation found that no New Zealand staff were implicated in the fraud; one locally engaged Chinese national has resigned."
Former business diploma student Roe Wang, 18, who has been served with a deportation liability notice, told investigators she did not know fraudulent documents had been used to support her application.
She has not been able to attend school since July, but is choosing to remain in New Zealand to appeal against her deportation orders.
"I am innocent, but if I leave the country now I will have a deportation black mark that may prevent me from getting a visa to study anywhere else in the world," Miss Wang said in Mandarin.
She said she had two other friends who were also in limbo because of the deportation notices.
"It is really wasting a lot of our time and costing a lot of money, but we really cannot do anything else without first clearing our names," she said.
Chiwi Immigration Services, an Auckland-based agency representing four other Chinese students who also face deportation, will be taking their appeals to the Immigration Minister.
Since the scam was uncovered in July, 31 students have left New Zealand and three have successfully had their deportation notices cancelled after making submissions to Immigration that they were not complicit in the fraud.
Immigration said deportation appeals were still being reviewed.