Cash-and-carry boss Roger Cooper and his brother David Cooper have both been found guilty at Birmingham Crown Court of the Christmas Eve murder of Costco marketing manager Sameena Imam.

Ilford Recorder: David Cooper, 39, pictured, and his brother Roger Cooper, 41, were convicted at Birmingham Crown Court of murdering Sameena Imam following a 10-week trial. Pic: West Midlands PoliceDavid Cooper, 39, pictured, and his brother Roger Cooper, 41, were convicted at Birmingham Crown Court of murdering Sameena Imam following a 10-week trial. Pic: West Midlands Police (Image: West Midlands Police)

Costco store boss Roger Cooper and ex-soldier David Cooper bought poisonous metals, identified a shallow grave and communicated in text messages written in a Star Wars-based code before killing Sameena Imam.

An eight-week trial at Birmingham Crown Court heard Roger Cooper spent at least a month plotting to kill the 34-year-old – one of his three lovers – to prevent her exposing their two-year affair.

Both Roger and David Cooper – who are 6ft 5ins and 6ft 7ins tall – remained calm and did not look at each other as they were unanimously convicted by a jury at Birmingham Crown Court.

Miss Imam, who was just 5ft 2ins, is believed to have been overpowered on a sofa at David Cooper’s home in Hughenden Drive, Leicester, between 5.07pm and 6.26pm on Christmas Eve after being driven to the property from Coventry by his brother.

The victim, who worked at Costco stores in Cardiff, Southampton, Bristol and Coventry, was reported missing by family members in Ilford after failing to return home for Christmas, sparking a major police inquiry.

Roger Cooper, 41, and his 39-year-old brother were arrested on suspicion of murder on January 7 – a week before Misss Imam’s body was found buried on an allotment in Leicester.

Post-mortem tests established the shop worker, who lived in Cardiff, was killed using chloroform.

A “bizarre” combination of metallic elements, including antimony, cadmium, tin, mercury and arsenic, is also thought to have been administered to Ms Imam in a liquid.

At the start of the trial, it was alleged that Roger Cooper was “juggling” relationships with three women, including Sameena and a second colleague, while managing Coventry’s Costco warehouse.

The retail worker, of Tilehurst Drive, Coventry, told police investigating Miss Imam’s disappearance that he last saw her when she left the store at about 4pm on December 24.

His brother told officers he did not even know Miss Imam’s name but later made a partial confession, claiming to have pressed a chloroform-soaked tea towel over her mouth.

Although the former signals regiment reservist claimed the death had been an accident, he later changed his account, telling jurors he found Miss Imam’s body after being asked to move a car.

But messages sent from a mobile phone linked to David Cooper – including Stars Wars-related phrases such as “Death Star complete”, “stay on target” and “look at the size of that thing” – proved the brothers had made a previous attempt on Miss Imam’s life in mid-December.

Roger Cooper admitted in court that a message reading “You are expected Vader” was a coded reference to Miss Imam but insisted it had been part of surveillance to check if she was seeing another man.

Other evidence used to convict the brothers, originally from Essex, included numerous automatic number plate recognition “hits” showing vehicles they had used travelling between Coventry and Leicester.

A bottle of Bellini bought in Coventry by Miss Imam on Christmas Eve was also found in the fridge at the home of David Cooper, whose allotment shed featured a sign reading: “Don’t wind me up... I’m running out of places to hide the bodies.”

Officers believe the plot on December 11 may have been aborted because Miss Imam arrived at a hotel in Solihull in a taxi and was dropped off within yards of the main entrance.

Evidence of a further suspected attempt to target the regional marketing manager on December 21 was also presented to the jury.

Det Ch Insp Caroline Marsh said: “I would say this is the most callous offence I have ever investigated.

“Most murders that occur are spontaneous events driven by anger or jealousy, whereas in this case what we uncovered was weeks and weeks of planning to kill Sameena, numerous attempts on her life and a really unusual cause of death.

“We very rarely see chloroform homicides. It’s been a particularly challenging case and a particularly complex investigation and we are extremely grateful to the jury, who have listened to the case and given us the verdict we’ve had today.”