The phrase "deployed in operation" is correct and usable in written English.
It refers to something being put into action or use for a specific purpose. Example: The new technology was successfully deployed in operation, greatly increasing productivity and efficiency within the company.
French soldiers deployed in Operation Sangaris in the Central African Republic have started leaving Bangui and moving into the provinces.
In May, his squadron was deployed in Operation Fire Bash, to attack Westerland Airfield on the island of Sylt.
The division was next deployed in Operation Market Garden and fought in the subsequent Battle of Arnhem.
More than 1.7 million American service members have been deployed in Operation Enduring Freedom in Afghanistan and Operation Iraqi Freedom in Iraq.
Between 1971 and 1982, about 1,500 men and women served aboard 34 C-123s that were previously deployed in Operation Ranch Hand.
He was deployed in Operation Enduring Freedom in Afghanistan, and received 11 medals in total, including for good conduct and combat action.
"Thousands of troops are being deployed in operations that are widening across the region".
Suspects arrested after flat siege Dozens of armed officers, some wearing gas masks and carrying machine guns, were deployed in operations in west London today that began mid-morning and involved elite plainclothes firearms officers and snipers from Scotland Yard's SO19 unit.
VICE News correspondent Simon Ostrovsky interviewed troops deployed in the operation at the border between Kharkiv and Donetsk, while the Ukrainian military launched an anti-terrorist operation to quell the pro-Russia violence and unrest that has swept eastern Ukraine.
An American spokesman, Lt. Col. Roger King, said hundreds of troops had been deployed in the operation, and a number of Afghans had been "taken in for screening".
The documents include warnings for officers deployed in an operation that's typically described as low-risk.
