A guest aboard a Carnival cruise ship was reported missing by family Monday morning, according to the Miami-Dade Police Department.

Kevin McGrath, 26, was on the Carnival Conquest with family and was last seen by his brother in his cabin early Monday, the day the ship arrived back to Port Miami, according to a spokesperson for Carnival Cruise Line.

McGrath was supposed to meet with family for breakfast before disembarking the ship, but he never arrived, Miami-Dade Detective Angel Rodriguez said in a statement.

After an extensive search, Carnival crew members were unable to find McGrath on the ship. The U.S. Coast Guard and the Miami-Dade Police Department were later called to investigate and searched the ship and the water for the missing man but failed to locate him.

Surveillance systems and the U.S. Customs and Border Patrol did not find McGrath once passengers were disembarking the ship, Carnival said. Miami-Dade authorities also checked security cameras, none of which indicated that he may have gone overboard, Rodriguez said.

McGrath's whereabouts are still unknown.

McGrath is 5-foor-9 and 170 pounds and was last seen wearing a black T-shirt, black shorts and gray sneakers.