PALGHAR, Aug. 22 -- Four workers died and two others were left battling for life after a nitrogen gas leak at a pharmaceutical unit in Tarapur MIDC, Palghar district, on Thursday afternoon. A nitrogen gas leak is extremely dangerous, primarily causing oxygen displacement and leading to asphyxiation (suffocation) by lowering oxygen levels, which can quickly lead to dizziness, loss of consciousness, and death. The incident occurred between 2.30pm and 3pm at Medley Pharmaceuticals' factory (F-13) in the industrial hub of Boisar, around 130 km from Mumbai. According to police and disaster management officials, nitrogen gas leaked from a reaction tank during the production of Albendazole, a medication used for the treatment of a variety of parasitic worm infections. After the leak was reported, six workers were suffocated at the site and were rushed to a private hospital in Boisar, where four were declared dead upon arrival. They were later identified as Kamlesh Yadav, Kalpesh Raut, Dhiraj Prajapati and Bangali Thakur. The two others - Rohan Shinde and Nilesh Hadal - remain in the intensive care unit in critical condition. "The leak led to a rapid reduction of oxygen in the immediate area, causing suffocation. Four workers were declared dead around 6.15pm," said Vivekanand Kadam, chief of Palghar district disaster management cell. Police said prima facie, the accident was caused by inhalation of nitrogen, though a detailed probe has been launched. Officials from the Directorate of Industrial Safety and Health (DISH) have also joined the investigation. "When gas leaked at the factory, the workers went to save a factory official. Due to this, they were badly affected. Two people are still undergoing treatment. The victims were brought to the hospital late," said a friend of a deceased. Authorities fear that the death toll may rise further as the situation remains serious. The exact cause will be determined after technical assessment of the nitrogen tank. A case has been registered, a police official informed. Officials said Kalpesh Raut is a resident of Chinchani in Dahanu, while Thakur hails from Patna in Bihar. Prajapati is a resident of Shivajinagar in Bosiar's Salvad area. Yadav hails from Azamgarh in Uttar Pradesh....