A police officer was stabbed in the face with a pen while arresting a man at a home in north London.
The female officer was attacked in the garden of a property in Manor Park Crescent, Edgware, on Sunday morning.
A Taser was used by officers to detain the 39-year-old man. Both have been taken to hospital for treatment, the Met Police said.
He was arrested on suspicion of breach of bail, as well as threats to kill and GBH against the police officer.