In a major breakthrough, the Tamil Nadu police has arrested the key accused in the Coimbatore serial blasts in 1998. The accused had set off the blasts minutes before a public meeting was to be addressed by BJP president L.K. Advani. The arrest came after a closely coordinated operation involving the state police.Acting on a tip-off, the Special Investigating Team arrested S.K. Mohideen alias Abdul Khader, who had been evading police for eight years, near Koodankulam in Tirunelveli district. According to police, 28-year-old Mohideen, besides being a ‘‘vital accused’’ in the Coimbatore blasts, was allegedly involved in the murder of three RSS sympathisers near Tirunelveli in August 1997. The youth was even to be used as a human bomb in the 1998 blasts that claimed more than 50 lives in the textile town.Police had been hunting for Mohideen in various parts of the country, including Mumbai and Bangalore. Mohideen was remanded in judicial custody and lodged in the Palayamkottai Central prison. He will be produced before the Coimbatore trial court.Among other key accused in the blasts is S.A. Basha, the leader of the banned Islamic fundamentalist group, Al Umma.