Police officers have reported being "bricked" and having rocks thrown at them while making an arrest in Bradford.
Officers were deployed to the Skinner Lane area of Manningham shortly before 6pm.
They were arresting someone suspected of drug driving.
Duty inspector Carlton Young said: "They stopped somebody and gone through to make an arrest.
"Somebody was throwing stones at them."
No further arrests were made in relation to the incident.
One of the officers, who goes by the name Traffic Dave on Twitter, posted: "Getting bricked in #Bradford now. Driver arrested for drug driving and officers get rocks lobbed at them. Further units deployed by @WYP_FCH."
It was the second time in one day the officer reported such an incident online.
Earlier he posted: "A brick was lobbed from Burdock Way #Halifax at colleagues who were in the vehicle underneath the flyover at the time."