Last month, a bomb explosion occurred in a ferry in Playa Del Carmen, injuring 26 people.
He also says that threats are nothing new, and haven't prevented people from traveling to other countries with warnings in the past.
"We released a March 7 Security Alert to all U.S. citizens due to credible information we received regarding this security threat in Playa del Carmen", a U.S. State Department official said in an email.
The U.S. Embassy in Mexico updated a travel warning for the Caribbean city of Playa del Carmen, narrowing the restricted areas government employees must avoid after an "ongoing security threat".
The U.S. Consular Agency in Playa del Carmen in the state Quintana Roo will be closed "until further notice", the embassy said in its alert.More news: Janhvi Kapoor indeed is a 'strong woman', resumes Dhadak shoot
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The alert, issued Wednesday night, says USA government employees have to cease traveling to the town "immediately" and "until further notice". Last week, another ferry was found to have undetonated explosives on board.
And while US citizens aren't explicitly forbidden to visit Playa del Carmen, if the consulate and embassy services are unavailable in a place you're planning to be, it's generally a good idea to head somewhere else. Why? The incident injured 25 people, including two Americans. Both incidents are still under investigation.
But the number of foreign visitors to the resort town jumped more than 18 percent a year ago, and CBS News travel editor Peter Greenberg says the number of Americans killed in violent crimes in Mexico is very small. "We recommend USA citizens planning travel to the area consider this information before making travel decisions". The alert system has put out a "Level 2: Exercise Increased Caution" alert. At the time, the warning cited potential risks associated with kidnapping, carjacking, robbery, and murder.
The alert comes just before many Americans plan to flock to Playa del Carmen for spring break, which typically takes places from mid-March to mid-April.
"We do not know why the USA government made a decision to emit this alert", the state government said. Other tourists reported blacking out after drinking at resorts in Mexico.