Hungarian police say the deceased captain of a tour boat which sank after colliding with a river cruise ship on the Danube River was not to blame.

Twenty-eight people, mostly South Korean tourists, aboard the Hableany (Mermaid) sightseeing boat died after their vessel collided with the Viking Sigyn river cruise ship on May 29. The remains of a South Korean tourist have yet to be recovered.

Col. Adrian Pal of the Budapest Police said Tuesday that tests showed that the Ukrainian captain of the Viking Sigyn, identified only as Yuriy C., was not under the influence of drugs or alcohol at the time of the incident.

Police Chief Colonel Adrian Pal, Deputy of the Budapest Police Commissioner holds an international press conference on the closed police investigation on the Hableany (Mermaid) boat accident on the River Danube in Budapest, Hungary, Tuesday, Oct. 15, 2019. The Hableany sightseeing boat carrying 33 South Korean tourists and two Hungarian staff crashed into the Viking Sigyn river cruise ship and sank in the River Danube in central Budapest on 29 May 2019. Seven South Koreans survived, the others died. (Tamas KovacsMTI via AP)

Police Chief Colonel Adrian Pal, Deputy of the Budapest Police Commissioner holds an international press conference on the closed police investigation on the Hableany (Mermaid) boat accident on the River Danube in Budapest, Hungary, Tuesday, Oct. 15, 2019. The Hableany sightseeing boat carrying 33 South Korean tourists and two Hungarian staff crashed into the Viking Sigyn river cruise ship and sank in the River Danube in central Budapest on 29 May 2019. Seven South Koreans survived, the others died. (Tamas KovacsMTI via AP)

Pal added that their recently-concluded investigation contained some 11,000 pages of documentation and over 4,200 photos.