MUMBAI, Feb. 4 -- A 26-year-old contract labourer died after being exposed to toxic fumes and a powerful surge of water while cleaning a deep sewer line in Goregaon in the early hours of Tuesday. The deceased, Shamim Razak Gazi, was engaged on a contractual basis for drain-cleaning work by the sewerage operations department of the Brihanmumbai Municipal Corporation. The incident occurred at dawn at a manhole near Gate No 2 of Mega Mall, close to the Goregaon pumping station beneath the metro lines. Gazi had descended nearly 25 feet into the manhole along with co-worker Shaheen Noor Islam, 36, to remove a blockage. Officials from the disaster management control room said Gazi is suspected to have died due to inhalation of toxic gases and being overwhelmed by a sudden gush of water inside the drain. Islam narrowly escaped death after being rescued in time by the Mumbai Fire Brigade. He was pulled out of the manhole and rushed to the Hinduhridaysamrat Bal Thackeray Trauma Care Hospital in Jogeshwari, where he is undergoing treatment. The BMC maintained that basic safety precautions were followed before the workers were sent inside. Civic officials claimed that oxygen and temperature levels inside the drain were checked and that the workers were equipped with protective gear. However, police officials who visited the spot said the situation turned dangerous once the blockage was disturbed. "A sudden release of toxic fumes and a strong water flow caught the worker off guard. He was overwhelmed by the fumes and the surge of water," a police officer said. Islam was retrieved first and taken to hospital. Gazi's body was recovered nearly two hours later and he was declared dead on arrival at hospital. Mohammed Imran Shaikh, the contractor assigned the work through Gypson Company, said Gazi had been working with him for barely a month and that he was unaware of his family background. A post-mortem was conducted at Siddharth Hospital in Goregaon West on Tuesday. Gazi's body was later handed over to a relative for last rites at his native village, Amodia, in West Bengal's 24 Parganas district. The relative was reportedly unwilling to file a complaint. An officer from Oshiwara police station said the case would be probed suo motu. "If any lapses or negligence are found, an offence will be registered," the officer said. Trade unions and former civic officials criticised the continued use of manual sewer cleaning. Maharashtra Municipal Kamgar Union general secretary Milind Ranade said the BMC was responsible for ensuring worker safety and compensation, regardless of contractual status....