NEW DELHI: India had tipped off Sri Lanka several times over the possibility of a jihadi attack and Indian agencies also pointed to National Thawheed Jamaat (NTJ) having a number of associates and followers in Pakistan.Indian intelligence has been tracking the influence of Wahabism, with its hardline Islamic beliefs, in eastern Sri Lanka and warned that the region could develop into an operational zone for Lashkar-e-Taiba and like-minded jihadi groups.The Pakistan link to violent groups in Sri Lanka was underlined by Lashkar's charity front Falah-i-Insaniyat advertising in 2016 its presence in the island nation apart from its activities in Syria, Afghanistan, Myanmar and Somalia. The NTJ has been seeking to harness a growing radicalisation, the seeds of which were sown by Lashkar and its 'charity' wing Idara Khidmat-e-Khalq. The latter was actively engaged in disaster relief activities in Sri Lanka and Maldives after a tsunami struck in 2004.The sustained attempts by LeT to build bases in Sri Lanka over the past one-and-a-half decade, as part of a broader design to "encircle" India, may have helped the growth of Islamic groups such as NTJ, now named by Sri Lanka to be behind Easter Sunday's serial blasts. India's warnings were perhaps not taken with due seriousness, said sources.According to Indian agencies, NTJ has been associated with Al Qaeda that has been radicalizing and recruiting young Sri Lankans for global jihad. Later, Sri Lankan youth were learnt to be training in camps in Pakistan. It is understood that intelligence agencies also expressed concerns over Thowheed Jamaat in Tamil Nadu over possible activities related to radicalization and a fundamentalist orientation.That Indian intelligence agencies had warned about an attack by the NTJ has been corroborated by New York Times which said Indian security agencies had shared "specific intelligence" about a plot by the jihadi group as early as April 4. But the daily suggested that the warning may have gone unheeded."The target selection and attack type make me very sceptical that this was carried out by a local group without any outside support," the NYT quoted Amarnath Amarasingam, a specialist in Sri Lankan extremism at the Institute for Strategic Dialogue, a counter-terrorism research group in London, as saying.Sources said LeT and LTTE go back to 1992 when they tied up for supply of weapons and training. LTTE, as per agencies, was the first to provide weapons to Muslim radical elements in Sri Lanka. Most of these weapons were taken back by the police, though some seemed to have slipped through.While the ISI is reported to have helped LeT develop safe houses, a Sri Lankan national Mohammad Sakir Hussain is currently under arrest after conviction in Chennai. He is alleged to be an ISI agent being run by a Pakistani diplomat Amir Siddiqui from Colombo. Siddiqui was working on a plot to attack the US consulate in Chennai as well as naval bases in south India with the help Hussain.LeT operative Faiyaz Kagzi, an accused in the 26/11 attacks but acquitted later, had trained German Bakery blasts case convict Mirza Himayat Baig in Colombo. At least 38 Sri Lankan youths are understood to have joined the IS. Around 200 Maldivians travelled to Iraq-Syria in 2014. Maldivian agencies also reported over 50 Maldivian youth trained at LeT camps in Pakistan.