A woman has been arrested in connection with the murder of a university graduate whose body was found in a burning car.

Catherine Wells-Burr, 23, was discovered in her red Ford Focus, which was abandoned in a field by the side of a road near Ilminster, Somerset.

A 32-year-old woman was arrested on Thursday night on suspicion of murder and remains in police custody. Two men also arrested have been eliminated from the inquiry, Avon and Somerset Police said.

Detective Chief Inspector Simon Crisp said: "A post-mortem will begin today to try and identify how Catherine died. We still need information from members of the public and those people who knew Catherine or knew of her. It is imperative we get a full picture of her life and you may have information that could help."

Firefighters were alerted to the blazing five-door vehicle shortly before 6.30am on Wednesday off the A358 in Ashill. Fire crews extinguished the flames and discovered the body of the Bath Spa University graduate inside the wreckage.

Avon and Somerset detectives earlier confirmed they are treating her "tragic and brutal" death as suspicious.

On August 25 Miss Wells-Burr updated the cover photo on her Facebook profile with a picture of a woman covering her face with a book. Accompanying the picture was the cryptic message: "You can't start the next chapter of your life if you keep re-reading the last one."

Detective chief inspector Simon Crisp, who is leading the investigation, said on Thursday: " I am making a double appeal today. Firstly for those people that may have witnessed Catherine and her red Ford Focus arriving at the scene which is alongside the A358 near Ilminster. Did anybody see that car arrive? Did anybody see suspicious people arrive or leave the scene at about 6am to 6.30am on a busy road? We need you to call us.

"The second part of the appeal is to help us understand Catherine's private and social life.

"Did she know her killer is the question that we're asking ourselves. Did she arrange to meet somebody at the location where she met her death? These are the things we are seriously considering. Please don't leave it to others to tell us, call us immediately."