A Suffolk rail passenger has described how a "brutal, shocking and surprising" unprovoked assault on a midday train has left her with cognitive impairments.

Kathryn Cain, 56, suffered a black eye and concussion when she was randomly attacked by a female passenger while travelling with her partner Angus Thody, 60, on the 12.28pm train between Felixstowe and Ipswich on Saturday, June 11.

She was critical of the response by British Transport Police (BTP) as she said she reported the incident to them immediately after arriving at Ipswich station, but as yet no action had been taken and the police were still waiting to obtain CCTV footage from the station.

The couple were heading for a day out in London, but became aware of a woman walking up the carriage who was behaving strangely and seemed "distracted", muttering and singing to herself.

As she approached their table in the otherwise empty carriage, she stumbled and lost her balance, but in the process reached across and punched Ms Cain in the face, causing severe bruising to her right eye.

Ms Cain said she watched as her assailant then calmly continued to walk to the next carriage where she waited for the door to open as the train approached the station before disappearing through the double barriers in the terminal building.

On arrival, she reported the incident to staff with train operator Greater Anglia who provided her with an ice pack for her face and suggested she call the BTP.

By chance, another passenger on the service knew her attacker and provided her with a name which she passed on to the police.

Ms Cain, who lives with her partner in High Road East, Felixstowe, added: “It did hurt, but my initial sensation was more a kind of shock at what had happened.

“After about 24 hours it really did hurt and my cognitive ability has been impaired, particularly my thinking ability, which my GP said is perfectly normal after a blow to the head. It was quite painful for about four or five days after the incident.”

Mr Thody said: “It is really just the brutality of it in broad daylight. If this has happened to us, it could happen to anybody and it is just shocking. We are nice people and we had not spoken to her or done anything to provoke her.

“In fact, I was about to ask if she was ok following her stumble, but before I had the chance to say anything, she punched Kathryn.”

A BTP spokeswoman said CCTV had not yet been received from the station.

She said: “Officers received a report of an assault onboard a train to Felixstowe on 11 June. Officers made contact with the victim that day and arranged to take a statement at her earliest convenience.

“Enquiries into the incident have been ongoing, which have included requesting CCTV footage from the train operating company.”

Any witnesses who haven’t already spoken to police can contact BTP by texting 61016 or calling 0800 40 50 40 quoting reference 2200057944.