Detectives are questioning a man over the attempted murder of two police officers in Aldershot.
The pair suffered serious injuries when they were assaulted after being called to a domestic incident in Pegasus Avenue on Tuesday evening, Hampshire Police said.
The officers were taken to Frimley Park Hospital and one was then transferred to St George's Hospital in Tooting, south London, where he is receiving specialist treatment for his injuries.
The other was discharged overnight.
A 41-year-old man from the Hampshire town was initially arrested on suspicion of wounding with intent but was rearrested on suspicion of two counts of attempted murder.
Police are appealing for witnesses or anyone with information about the "isolated incident" to come forward, and have carried out house-to-house inquiries.
Detective Inspector Sion Margrie said: "There would have been people in the area at the time of the incident and it is likely someone saw or heard what happened, or even filmed the incident on their mobile phones.
"We want to speak to anyone who was there or has any other information that could help."
Hampshire Police Federation chairman John Apter said: "It is terrible news that these two officers have been badly assaulted.
"We wish them both a full recovery and we will offer them all the support necessary. Our thoughts and prayers are with the officers and their families."