Here are the full statements from temporary Chief Constable Dee Collins of West Yorkshire Police and Mark Burns-Williamson, West Yorkshire’s Police and Crime Commissioner:
Temporary Chief Constable Dee Collins said: “I would like to provide an update in respect of the tragic events of yesterday, where our local MP for Batley and Spen, Jo Cox, was brutally attacked in Market Street, Birstall.
“We have now confirmed that just before 1pm yesterday Jo arrived in a vehicle in company with two colleagues outside the library on Market Street, and whilst en-route to the library where she had a scheduled constituency meeting, she was attacked and sustained serious injuries from both a firearm and a knife, and despite assistance from passers-by, the ambulance service and police officers who were quickly on the scene, she sadly died of her injuries.
“During the course of the incident a 77-year-old man bravely intervened to assist Jo and in doing so sustained a serious injury to his abdomen, and although now stable he remains in hospital.
“We have had overwhelming support from the public in respect of this incident, which assisted us in quickly locating a suspect who was tackled by unarmed officers and arrested.
“A murder investigation is under way by West Yorkshire Police, who are working together with the North East Counter Terrorism Unit, who will bring specialist assets in support of the inquiry.
“We are aware of the speculation within the media in respect of the suspect’s link to mental health services and this is a clear line of inquiry which we are pursuing.
“We are also aware of the inference within the media of the suspect being linked to right wing extremism which is again a priority line of inquiry which will help us establish the motive for the attack on Jo.
“We are keeping an open mind and I do not wish to add to the speculation as we need to ensure that we conduct a professional investigation and do not compromise the need to bring the person responsible to justice.
“Based on information available at this time, this appears to be an isolated, but targeted attack upon Jo - there is also no indication at this stage that anyone else was involved in the attack. However we will be investigating how the suspect came to be in possession of an unlawfully held firearm.
“We are aware of two previous unrelated incidents which culminated in Jo receiving a malicious communication of a sexual nature at her parliamentary office in Westminster. Both incidents were investigated by the Metropolitan Police Service, which resulted in an individual receiving an adult caution for one offence, which I can confirm is not the same person who we have in custody. The other incident remains un-detected. West Yorkshire Police have not been made aware of any complaints or concerns from Jo Cox.
“The suspect in custody has been medically examined by two specialist medical practitioners who have determined that he is both fit for detention and fit for interview and detectives will continue to question the suspect during the day.
“This remains an active investigation, with a number of scenes which are being forensically examined, including the suspect’s home address. There are numerous lines of ongoing inquiry. We appreciate this has caused some disruption, which will go on for some time, but I would ask people to bear with us while we carry out this critical work.
“This has clearly had a huge impact on the community and we are grateful for their support and cooperation and that of our partners at this time.
“Yesterday and today, officers have been working in and supporting the local community and will continue to do so in order to provide reassurance and maintain public confidence.
“We have been engaged nationally with the Palace of Westminster and the Home Office to review the security arrangements of MPs generally and we are continuing to provide the appropriate advice and guidance to MPs both locally and nationally and seriously considering any concerns which they may have. However all indications are that this is a single isolated attack on Jo, for reasons that we are still trying to establish.
“I would like to thank the media for the way in which they have respected the family’s wishes for privacy at this tragic and sensitive time and I hope this continues.
“Finally I would like to reiterate my sincere condolences to Jo’s husband Brendan, their young children and their wider family, friends, colleagues and the community in which she served - all of which have been deeply affected by Jo’s senseless and tragic death.”
Mr Burns-Williamson said: “Firstly, I want to restate my deep horror and revulsion at the senseless taking of Jo Cox’s life, which has devastated her family and friends and her community. My condolences and thoughts continue to be with her family.
“Being at the church vigil and witnessing the huge impact this tragedy is having on Batley and Spen, and nationally and internationally demonstrates what a very special person Jo was to so many.
“At the moment we have an ongoing criminal investigation into the circumstances that led to Jo’s untimely death and it is crucially important that we let the police carry on doing their job to ensure justice for Jo’s family, her colleagues and the wider community.
“I would also like to extend my thanks for the brave and quick actions of the officers who apprehended the suspect nearby.
“It is totally understandable that people will want answers to valid questions around what led to this tragic incident, and those answers, I have no doubt, will come in due course. But it is crucially important that we ensure that potential criminal proceedings, charges and due process is not jeopardised in any way.
“I want to reassure people that I will do everything within my power as Police and Crime Commissioner, with West Yorkshire Police, to ensure the people of Batley and Spen, and communities across West Yorkshire are safe and feel safe at this difficult time.”