Aaron Hernandez Trial: How Prosecutors Linked the Former Patriots Star to Murder

— -- A Massachusetts detective testified that bubble gum was found attached to a bullet shell casing that was recovered from a car Aaron Hernandez had rented -- evidence, prosecutors say, that linked him to the murder of Odin Lloyd.

North Attleborough Police Det. Michael Elliott said they were called by a rental car company employee, who told them that several items had been removed from a car Hernandez rented and put in a trash bin.

Elliott said investigators searched that garbage bin and found the spent shell casing attached to the piece of gum.

Throughout the trial, the defense has questioned how police handled evidence in the case.

Hernandez, 25, bought Blue Cotton Candy Bubblicious gum at a gas station just hours before he allegedly shot Lloyd in an industrial lot at 3 a.m. on June 17, 2013, prosecutors have said in court documents.

After Elliot's testimony, a rental car company manager supported the police's account, testifying today that she found a shell casing inside a vehicle Hernandez had rented.

Keelia Smyth, who worked at Enterprise Rent-a-Car at the time, said she found the bullet casing while cleaning the rented Nissan Altima after the former NFL star had returned it. Not knowing Lloyd had been murdered, she said she put the shell casing she found -- along with some chewed blue-colored gum and a bottle of Vitamin Water -- inside a trash bin.

Smyth said she didn't realize the importance of the car or its contents until she saw media reports of Lloyd's murder. That's when she called the police, who recovered the gum and shell casing.

The defense questioned the findings, saying that Hernandez's DNA may have transferred to the gum in a state police lab.

On Tuesday, prosecutors played a police surveillance video of the former NFL star allegedly dismantling his phone while inside a rental car a day after Lloyd's death.

Before playing the video, Elliot had testified that a few hours after Hernandez left the police station, he saw the former New England Patriots player from the closed-circuit police camera sitting in his lawyer's car, breaking down his cell phone.

On cross examination, Elliot conceded that Hernandez did not smash his Blackberry, but instead had just slid the back cover to take out the battery.

Prosecutors claim Hernandez used the phone to call co-defendant Ernest Wallace.

Lloyd, 27, had been dating Hernandez's fiancee's sister at the time of his death.

The Associated Press contributed to this report.

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