New Delhi, March 20 (IANS) Concerned over increasing incidents of unnatural deaths of tigers in various reserves in the country, Prime Minister Manmohan Singh has decided to personally take up the matter with state governments, Environment Minister Jairam Ramesh said Saturday.

The prime minister expressed his concern during the meeting of National Board for Wildlife Thursday, Ramesh told reporters here.

'The prime minister has agreed to lend weight of his office for monitoring state governments. He will also take up the matter with the chief ministers of various states, especifically with the Uttarakhand government, as unnatural mortality of tigers have been reported from Corbett National Park,' he said.

According to Ramesh, 11 tigers were killed in first two months of 2010 while 66 tigers were killed last year.

'The normal mortality of tiger in a year is 30 but 66 were killed in 2009. Of these, 46 were killed inside tiger reserves while 20 were killed in forests. People from mafias to local politicians and many others are involved in it as they want the tiger population to dwindle so that the land can be used for mining or construction,' he added.