WASHINGTON (CNN) -- The Pentagon said Monday that Chinese ships harassed a U.S. surveillance ship Sunday in the South China Sea in the latest of several instances of "increasingly aggressive conduct" in the past week. The Navy says this photo shows two Chinese trawlers forcing the Impeccable to make an emergency "all stop." During the incident, five Chinese vessels "shadowed and aggressively maneuvered in dangerously close proximity to USNS Impeccable, in an apparent coordinated effort to harass the U.S. ocean surveillance ship while it was conducting routine operations in international waters," the Pentagon said in a written statement. The crew members aboard the vessels, two of which were within 50 feet, waved Chinese flags and told the U.S. ship to leave the area, the statement said.
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State Department says U.S. Embassy in Beijing has lodged protest
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U.S. surveillance ship was in international waters, Pentagon says
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Pentagon says vessels came "dangerously close," so U.S. ship sprayed fire hoses
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Statement: Chinese crew stripped to underwear, tried to snag acoustic equipment
Impeccable
USNS Impeccable
After the @placeholder alerted the Chinese ships "in a friendly manner" that it was seeking a safe path to depart the area, two of the Chinese ships stopped "directly ahead of USNS Impeccable, forcing Impeccable to conduct an emergency 'all stop' in order to avoid collision," the statement said.
Navy
The 281.5-foot Impeccable is one of six surveillance ships that perform military survey operations, according to the @placeholder.
Navy
It carries a crew of 20 mariners, five technicians and as many as 20 @placeholder personnel.