(CNN) -- The United Nations envoy to Ukraine who was threatened by armed men in Crimea on Wednesday told CNN he hopes his experience "serves as a reminder to all how dangerous the situation has become."
Robert Serry said the car he was traveling in was blocked by armed men in camouflage uniforms, who did not identify themselves, after he visited the headquarters of the Ukrainian navy in Simferopol.
The men told Serry they had orders to take him to the airport immediately, but Serry refused. A brief standoff ensued. The men pulled Serry's driver out of the car, and some managed to get in, the envoy said. He got out.
Serry walked and sought refuge for hours in a cafe, swarmed by protesters. He was eventually taken safely to the airport and left the country.
While he told CNN's "The Situation Room with Wolf Blitzer" he was not in fear for his life, the incident shows the "very urgent need to de-escalate" the tensions.
"All those who are responsible and can do that must have cool heads, lower their rhetoric, and address the situation. I'm very, very afraid for what could happen if there is bloodshed," Serry said from Istanbul, Turkey.
He was in Crimea at the behest of the U.N. secretary-general to report on what's happening there.
When asked by Blitzer what he believes need to be done, the envoy replied the situation on the ground needs to be addressed first.
"A mechanism is very much needed between the parties involved on the Crimea to actually start to control the situation and to de-escalate these tensions. There can be help from the outside if the parties accept that," he said.
"What is, of course, also very important is that a political dialogue starts between representatives from the Republic of Crimea and the government in Kiev."
Serry said Ukraine could be pulled apart if the rhetoric between the East ad West continues to rise.
The incident was mentioned Wednesday by the U.S. Secretary of State, who met with his Russian counterpart in Paris.
"We have seen today with what happened with Special Envoy Serry, just how important it is to ensure the safety of those monitors and observers," John Kerry said. "Ukraine's territorial integrity must be restored and must be respected. The United States stands ready to help our friends in a time of need."
CNN's Catherine E. Shoichet contributed to this report.
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