Zaheer Hussain, arrested on March 28, took out a blade and slit his throat when he was produced in the judicial magistrate court at Tirumangalam, near Madurai, in connection with the case, police said.
He suffered minor cut injury and was immediately rushed to hospital by police personnel present, they said.
This is the second time that Hussain attempted suicide in the court. Earlier, he tried to cut his hand after the magistrate rejected his appeal to discharge him from the case in April.
Police have registered a case against him then and now also for attempt to commit suicide.
He was arrested in connection with the planting of the bomb under a bridge at Alampatti near Tirumangalam which was found and defused by police hours before Advani was to pass through the road on October 28, 2011.
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