A German aid worker kidnapped in India is unharmed and will be released this week, the tribal separatist group holding him said yesterday. But they warned security forces against a rescue mission as it could 'endanger his life'. 'We are investigating the credentials and integrity of the German national and the process might take another five to six days,' a spokesman of the outlawed Kuki Liberation Army (KLA) said in the northeastern state of Manipur. KLA militants abducted Heinrich Wolfgang, a Bonn-based aid worker, on March 23 from Maphou village, 30km east of Manipur's capital Imphal. He had been on his way to oversee a community development programme funded by a German non-governmental organisation involved in relief and rehabilitation work for refugees displaced by violent ethnic conflict between tribal Nagas and Kukis in Manipur. 'There was discrimination against the tribal Kukis in the implementation of the development programme and so we have abducted him,' the spokesman said. 'We would like to assure that no harm will come to the German national while in our custody.' The rebel group refuted reports it had demanded 10 million rupees (about US$200,000) as ransom. Mr Wolfgang is the first foreigner to be targeted in Manipur by insurgents who have been demanding political autonomy and battling Indian security forces for years. India's north-east has been plagued by armed rebellion for half a century but only once before, in 1991, has a foreigner been kidnapped.