A Swedish diplomat who was recently questioned by police on suspicion of espionage has died, the man’s lawyer said on Friday.

Sweden’s SAPO security service captured an individual on Sunday, detaining him for questioning until Wednesday when he was released, yet he remains under investigation, according to the country’s prosecution service.

“I heard the tragic news this morning and my thoughts go to his family,” his lawyer, Anton Strand, told Reuters.

Strand declined to comment on the cause of the man’s death.

Police told daily Svenska Dagbladet they had opened an investigation into the death, but “there is no suspicion a crime has been committed.”

The man had denied any wrongdoing and had made a complaint against the police over the handling of the case, Strand said.

He also sought medical help after his release from custody.

According to public broadcaster SVT, the detained diplomat had been stationed at numerous Swedish embassies, and SAPO is probing a possible link to the recent resignation of the government’s national security adviser.

Sweden’s foreign ministry confirmed that one of its employees had died but declined to comment further.

“We must sadly confirm that an employee of the foreign service has passed away,” the ministry mentioned in a statement to Reuters. “To respect the family’s privacy, we will not disclose further details.”