In a disturbing and mysterious development, more than a tonne of fish were found dead in a lake at Taramatipet of Abdullapurmet in city suburbs on Monday. While local fishermen suspect foul play and allege that unidentified persons could have laced the water with poisonous substances, Fisheries Department officials maintained that the fish could have died due to depleting oxygen levels in the water because of the rising day temperature. Fishermen Karmika Sangham general secretary Ch Shankar said a group of people, who went for fishing, noticed the dead fish floating in the lake and alerted Fisheries officials and Hayathnagar police. Our families have been fishing in this lake for several decades. But this is the first time that something like this is happening, Shankar said, adding that the incident had led to a loss of over Rs 10 lakh for the fishing community in the area. Close to 100 families eke out a livelihood by catching fish from the lake and sell the same at the fish market in Dayara, Musheerabad, he said, adding that the State government should provide compensation to the community. Fisheries Department district officer M Rajaram said the fish could have died due to a dip in oxygen levels in the lake. We are advising the community to sell fish in summer once its weight reaches one kg instead of waiting till it reaches five kg, he said. The fish that died in Taramatipet lake weighed over five kg. Rajaram said a proposal relating to sanction of compensation to the affected families was already forwarded to the Commissioner. Based on a complaint from the fishermen, the Hayathnagar police registered a case, collected samples from the lake and sent them to the Forensic Science Laboratory (FSL) to ascertain the reasons behind the incident. A few days ago, fish worth over Rs 5 lakh died in a similar manner at Polkampally village in Ibrahimpatnam.