A court in the southern Indian state of Tamil Nadu has sentenced 23 people to life in prison in connection with a series of bombs nine years ago.
LK Advani was the alleged target of the bombs
Among those sentenced was the man described as the mastermind of the plot, SA Basha.
Nineteen bombs went off in the town of Coimbatore on 14 February 1998 just before Hindu nationalist leader LK Advani was due at an election rally.
Some 58 people were killed in the blasts which caused chaos in the town.
In all 166 people faced charges of being involved in the blasts, and around 153 have been found guilty.
Basha, the founder of the banned radical Muslim group, Al-Umma, is the most high profile defendant to be sentenced.
In August, another prominent defendant, Abdul Nasser Madani, the leader of the Kerala-based People's Democratic Party, was acquitted.
The 1998 bombings sparked clashes between Hindu and Muslim mobs in Coimbatore, some 2,400km (1,500 miles) south of Delhi.
The bombs went off close to where Mr Advani was due to speak.
At the time, he was president of the Hindu nationalist Bharatiya Janata Party (BJP). He was not at the podium when the bombs went off because his flight had been delayed.
Coimbatore was also the scene of Hindu-Muslim clashes in November 1997 after two men belonging to a radical Muslim group allegedly killed a Hindu policeman.
At least 17 people died in the violence that followed.
Investigators said that the bomb blasts were part of a conspiracy to assassinate Mr Advani to avenge the killing of the Muslims.