JEDDAH: A British teenager has admitted that he killed 31-year-old Saudi doctoral student, Nahid Almanea, by stabbing her 16 times as she walked from her student accommodation along the Salary Brook Trail toward the University of Essex on the morning of June 17, 2014.

The 17-year-old, who cannot be named for legal reasons, also pleaded guilty to the murder of James Attfield, 33, a father of five, by stabbing him over 100 times.

Almanea, who was wearing hijab, was killed just months after moving to Britain for her Ph.D.

Attfield was killed while walking along a riverside path in what police described as one of the most brutal attacks they had ever seen, with his attacker stabbing him 102 times, on March 29, 2014.

Almanea was walking on a footpath in the Salary Brook area of Colchester when she was stabbed in the head and body, three months later on June 17.

She was found lying in a pool of blood just six months after she had moved to the UK to study.

Dressed in a grey suit and black leather jacket, the bespectacled defendant admitted to the killings in court on Friday.

The teenager, from Colchester, was arrested after he was found with a knife on May 26 last year in the same area that Almanea was killed.

The University of Essex student, who was living in the town, was wearing a dark navy-blue abaya, or full-length robe, when she was attacked.

Following the stabbings, Essex police said there were striking similarities between the killings of Attfield and Almanea but nothing to link the victims.

At the height of their investigation, more than 100 detectives, uniformed officers, community support officers and civilian staff were involved. A number of people were also arrested.

A murder trial has already been fixed to start on April 11, at a venue yet to be decided.