Indian troops screened 30,000 men in a search for Tamil rebels and detained 131, India's chief diplomat in Sri Lanka said. Ambassador J. N. Dixit said that nine suspected rebels died in the operation. He added that some rebels probably eluded Indian forces during the sweep that began Thursday in the Batticaloa district, 140 miles northwest of Colombo. Similar searches are under way in the Vavuniya district in the north and the Trincomalee district in the northeast. Meanwhile, a curfew imposed by Indian troops in and around Batticaloa was lifted for 12 hours, and shops and businesses were crowded with people.