Andrew Sadek
Twenty-year-old Andrew Sadek became a police drug informant after his arrest for the sale of marijuana. He was later found dead with a bullet wound to the head. Facebook/'Justice for Andrew Sadek'

The 2014 death of a North Dakota university student is raising questions over the use of young, low-level drug offenders as police informants.

Andrew Sadek, a 20-year-old College of Science in Wahpeton student, was found in the Red River with a bullet wound to the head, wearing a backpack filled with rocks in June 2014, the Huffington Post reported.

A report released in February 2015 revealed that Sadek had signed up to become a confidential drug informant for the Southeast Multi-County Agency Drug Task Force following his arrest for selling marijuana to a police informant. The two transactions, totalling $80 (£53.55), were considered major felonies because they occurred on the school's campus.

The report revealed that the university student sold drugs for the task force from November 2013 to January 2014. He was later reported missing in May.

Following the report's release, Sadek's mother told reporters it backed up her belief that her son had been killed. "He was murdered," Tammy Sadek told KFGO. "This [report] actually reinforces that in our minds. We know that, and we know they're not even looking at anything....Did somebody he was trying to get for them do it? Or somebody he already got?"

However, the report released by North Dakota and South Dakota state crime bureaus and a Cass County sheriff's detective found the task force had acted appropriately in its partnership.

Renewed questions have emerged over the use of confidential informants in the drug world.

American Civil Liberties Union spokeswoman Jennifer Cook told the Associated Press that informants do dangerous work without being trained. "The safety risks associated with informant use can far outweigh the benefits," she said.

According to AP, authorities have not concluded whether Sadek was murdered or if he committed suicide. The fact that a gun that fires the same caliber bullet that killed the 20-year-old is missing from his family farm is not helping matters.