Story highlights Yakub Memon loses last-ditch appeal against death sentence for role in Mumbai bombings

53-year old charged as key conspirator behind 12 blasts that ripped through several hotels, marketplaces

Amnesty International criticizes India's use of the death penalty

(CNN) The man considered to be the mastermind behind coordinated bomb attacks in Mumbai in 1993 that left 257 people dead has been executed.

Yakub Memon was hanged at a prison in the western state of Maharashtra at around 6.30 a.m. local time, Indian Home Ministry spokesman Kuldeep Dhatwalia told CNN Thursday.

In the hours before the execution was carried out, a group of prominent lawyers contacted India's chief justice to seek a postponement of Memon's hanging for two weeks -- a day after Indian President Pranab Mukherjee rejected a final plea for mercy. They argued this was the minimum period of time required between the final appeal and execution.

In an unprecedented move, the Supreme Court held a special early-morning session to discuss the request before rejecting it, Dhatwalia said.

Memom died on his 53rd birthday.

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