The Idaho medical center CEO found dead in a Baltimore hotel over the summer died of methamphetamine intoxication, according to the Office of the Chief Medical Examiner.

The medical examiner’s office classified the manner of death as “undetermined,” meaning there wasn’t enough evidence to “classify the death as natural, suicide, homicide or accident,” Stephanie Moore, a spokesperson for the office, said in a statement.

“There has to be clear, undisputed evidence for anything else,” Moore said.

Nicholas Manning, 46, was the CEO of West Valley Medical Center in Caldwell, Idaho, and was studying health policy and management with the Johns Hopkins Bloomberg School of Public Health. He was in Baltimore in June, attending a meeting for a Ph.D. program, his family said in a post on social media.

Baltimore Police responded to the 700 block of Aliceanna Street on June 6 for a reported overdose. Manning was pronounced dead at the scene.

On Wednesday, the department said the case is under investigation as an overdose.

Over the summer, Manning’s family issued a statement saying they believed he was the victim of homicide and fraud. Baltimore Police have not shared any information to substantiate the family’s claim. The family didn’t immediately respond to a request for comment on Wednesday.

A company spokesperson for West Valley Medical Center said in a statement in June that Manning was a “dedicated and mission-driven leader who loved connecting people to our shared purpose.”