As many as 23 theft cases have been registered at the airports in the national capital and Mumbai this year till June, the government said today. During this period, 16 theft cases were registered at the Delhi airport while seven were registered at the Mumbai aerodrome, according to the data provided by Minister of State for Civil Aviation Jayant Sinha to Lok Sabha. Last year, the two airports together saw registration of 86 theft cases. In a written reply, Sinha said various steps are being taken to prevent such incidents even as he noted that theft cases are a "law and order issue". These include frisking of ground handling staff while leaving the airport and prohibition of cell phone use in the airside by ground handling people. Besides, a "committee has been constituted to identify the grey areas of CCTV coverage," Sinha said. In a separate written reply, Sinha said steps are being taken to control air traffic congestion at airports. "AAI has initiated the process for installation of Central Air Traffic Flow Management (C-ATFM) at six metro airports (Delhi, Chennai, Kolkata, Mumbai, Hyderabad and Bangalore) and associated air spaces in the first phase," he noted. Further, the Minister said supply, installation, testing and commissioning of first phase of C-ATFM project has been awarded with an estimated cost of Rs 107 crore. "C-ATFM is for the purpose of balancing the demand and capacity at airports and airspace. There is no implication on navigational facilities at Indian airports," Sinha said. The Minister, in another written reply, said 14 more airports have been taken up for energy audit in current fiscal. In 2015-16, energy audit was conducted at 42 airports.