Story highlights

NEW: Three defendants deny conspiracy to commit burglary and will face trial in November

Four -- John Collins, Daniel Jones, Terence Perkins and Brian Reader -- plead guilty

Gems, cash were stolen from a safe deposit firm in London's Hatton Garden area in April

London CNN  — 

Four men pleaded guilty Friday, admitting their role in a spectacular heist in the heart of London’s jewelry district.

Quantities of gems and cash were stolen from a safe deposit company in Hatton Garden over the four-day Easter holiday.

John Collins, 74, Daniel Jones, 58, Terence Perkins, 67, and Brian Reader, 76, each pleaded guilty to conspiracy to commit burglary during a hearing Friday at Woolwich Crown Court.

Three more defendants – Hugh Doyle, William Lincoln and Jon Harbinson – denied conspiracy to commit burglary and will face trial starting November 16.

They also face a charge of conspiracy to convert or transfer criminal property between April 1 and May 19.

Prosecutors decided not to pursue that charge against the four defendants who entered guilty pleas Friday.

Police haven’t given a precise value for what was taken from the vault of Hatton Garden Safe Deposit Ltd. Estimates reported by British media at the time ranged from hundreds of thousands of pounds to £200 million, or $300 million.

Investigators said the thieves appeared to have gained access to the basement vault through an elevator shaft, using a drill to bore through a 6-foot wall to reach the safe deposit boxes.

Following the raid, the Metropolitan Police Service said it was examining why the force did not respond despite being made aware a burglar alarm had gone off at the premises on April 3.

How a heist is masterminded