Ian Squire: Who was the British hostage killed in Nigeria

The 56-year-old optician from Surrey had developed a solar-powered portable lens-grinding machine

A British man who was taken hostage and killed in Nigeria had travelled to the country to help set up a new eye-care clinic.

Ian Squire was one of four British charity workers out in the rural community of Enekorogha.

The 56-year-old was an optician from Surrey and had developed a solar-powered portable lens-grinding machine for the clinic.

He had been working with the health charity New Foundations and was training local people to carry out sight tests and dispense prescription glasses.

The circumstances surrounding the abduction of the workers and Squire's death were not immediately clear, but Nigeria has one of the world's highest kidnap rates.

Previously however, militants have usually targeted oil workers, as several armed groups in the country have fought for a greater share of the control of the lucrative business.

A UK Foreign Office spokesman said: "We are supporting the families of four British people who were abducted on October 13 in Nigeria, one of whom was tragically killed.

"This has clearly been a traumatic time for all concerned, and our staff will continue to do all we can to support the families.

"We are grateful to the Nigerian authorities, and are unable to comment given the ongoing nature of their investigations."

Mr Squire was kidnapped alongside fellow charity workers David and Shirley Donovan and Alanna Carson.

They were abducted from their accommodation in Delta State in the south of the country in the early hours of 13 October.

In a statement, the families of the four hostages said: "Alanna, Ian, David and Shirley were kidnapped in Nigeria some three weeks ago.

"We are grateful for the support received by the British High Commission and help from the Nigerian authorities in negotiating their release.

"We are delighted and relieved that Alanna, David and Shirley have returned home safely. Our thoughts are now with the family and friends of Ian as we come to terms with his sad death.

"This has been a traumatic time for our loved ones who were kidnapped and for their families and friends here in the UK. We would therefore ask that the media respect our privacy as we come to terms with the news. We will not be making any further comment."