Chief Constable Gary Roberts says attacks on police officers are unacceptable - after ten assaults in the last month.
He took to Twitter after two assaults on female officers in just three days.
Mr Roberts says the latest officer to be targeted wasn't seriously injured, but says the attacks won't be tolerated.
Last month, it emerged six officers had been attacked by criminals in just five days.
What's wrong with people? Female officer assaulted overnight - she's OK - but that's the second such assault on a female officer in three days. We've now had ten assaults in the last month. Simply not acceptable.— CC Gary Roberts (@CCGaryRoberts) February 27, 2018