San Francisco, March 31 (IANS): US lawmakers of at least eight states are trying to mandate a "kill switch" for smartphones in an attempt to reduce the instrument's thefts and robberies, media reported.

Lawmakers in Connecticut, Illinois, Mississippi, Missouri, New Mexico, New York, Oregon and Virginia are working on draft legislations to authorise introduction of a software in newly-manufactured smartphones that can remotely disable stolen or lost devices, making them worthless to thieves or robbers, Xinhua news agwency reported.

California and Minnesota were the first two US states to adopt rules requiring smartphone manufacturers to make the "kill switch" function available in every device. Those bills will be put into effect on July 1 this year.

Reports said last month that three cities, namely San Francisco, New York and London, saw dramatic decline in smartphone thefts and robberies since the wireless industry began to include the "kill switch" on their devices, under Secure Our Smartphones (SOS), an international law-enforcing partnership initiative aimed at detering thefts.

Despite initial opposition from major US wireless carriers, who were particularly against state level mandate for the technology, some of them are now willing to introduce similar solutions to curb phone thefts.

Lost and stolen mobile devices in 2013 were estimated to have cost US consumers over $30 billion.