Delhi’s Tis Hazari Court on Thursday sent the four men arrested in connection with the Staff Selection Commission exam paper leak to seven days in police custody, ANI reported. The commission conducts exams for recruitment to the central government’s various departments, and the leak came to light after thousands of students protested in Delhi against “mass cheating” during the exam.

The police arrested the four men on Tuesday night. They found that the men allegedly hacked into the systems of the Staff Selection Commission, leaked the question paper and helped candidates solve them.

The accused took remote access of candidates’ computers and helped them in the exam, Senior Superintendent of Police (UP Special Task Force) Abhishek Singh said, according to the Hindustan Times.

This method of cheating was possible as the commission conducts its exams online. The exams are held in private computer labs across the country. “The men are suspected to have contacts with some of these computer labs,” the Hindustan Times quoted an investigator as saying.

The accused allegedly hired 150 people to hack into the system, access the question papers and solve them, the police said. They charged each candidate they helped Rs 10 lakh to Rs 15 lakh, according to reports.

The four men were arrested weeks after job aspirants protested against alleged “mass cheating” in the SSC exams. They claimed that the questions for an examination conducted on February 21 were leaked. The government has ordered an inquiry by the Central Bureau of Investigation.

On Tuesday, the Uttar Pradesh Police and the Delhi Police arrested the four men and busted the racket in a joint operation in the Capital. The teams seized a laptop, 10 mobile phones, three cars, dongles, documents and Rs 51 lakh in cash.