The U.S. Centers for Disease Control and Prevention has announced that an unknown illness sickened several people aboard a cruise ship earlier this month.

More than 140 people aboard Royal Caribbean's Navigator of the Seas suddenly got sick with vomiting and diarrhea during a round-trip cruise from Los Angeles to Mexico. The outbreak affected 134 passengers and seven crew members after the ship departed from LA on July 4.

The mystery gastrointestinal illness broke out onboard the Navigator of the Seas, a Royal Caribbean ship, on a round-trip to from the US to Mexico. Some 134 of the 3,914 guests fell ill, along with 11 crew members. Symptoms included sickness, abdominal cramps and diarrhoea.