A police officer has been attacked by two men after carrying out a "routine stop" on a car.
The Dyfed-Powys Police officer was taken to hospital as a precaution after suffering cuts and bruises.
The force said the PC stopped a car in Synod Inn, Ceredigion, at about 13:15 GMT and was assaulted by the two men inside.
Both ran away on foot and a manhunt, including the armed response unit and police helicopter, is under way.
A force spokeswoman said the men had not yet been found.
The suspects are white - one has a stocky build and was wearing jeans and a black T-shirt. The other was wearing a blue and yellow or white boiler suit.
Ch Supt Pete Roderick said: "We have reason to believe these two men will try to access a vehicle to leave the area, and are urging people to make sure they remove their keys and keep all vehicles - both domestic and farm equipment - locked.
"We are appealing for anyone who sees any men acting suspiciously - perhaps trying vehicle doors, or crossing farmland - to call 999 immediately.
"It is unacceptable that one of our colleagues was assaulted during the course of his duty and we are giving him the support he needs."
Paramedics were called by police to the scene at 13:25 and took the officer to Glangwili Hospital in Carmarthen.
BBC Wales reporter Aled Scourfield, who was at the scene, said officers with semi-automatic firearms and wearing protective helmets were patrolling the area.
Darren Taylor, who lives nearby, said: "There was a big number of police vehicles and the helicopter was flying low - like they were searching for someone.
"I'd never seen something like it before. People were quite anxious."