Thane, Feb 13 (PTI) Maharashtra Urban Development Minister Eknath Shinde has received a letter allegedly sent by Naxals, threatening to avenge the killing of their cadres in the state's Gadchiroli district, sources said on Sunday.<br> The letter was sent to the residence of Shinde, who is also the guardian minister of Thane and Gadchiroli, here on Friday, following which his security was heightened, a district official said. <br> The minister later said development was the only way to tackle the Naxal menace in Gadchiroli.<br> In November last year, 26 Naxals, including one of their top commanders, were gunned down in an encounter with police in Gadchiroli district.<br> According to the official, a complaint received by the Thane police in connection with the threatening letter has been handed over to the crime branch for an investigation. <br> Talking on reporters here on Saturday night, Shinde said he received such threats earlier also.<br> "As the guardian minister of Gadchiroli, it is my duty to take care of the district. Our aim is all-round development of the district and to bring it into the mainstream. Development of infrastructure is the only way to fight Naxalites in the region," Shinde said. PTI COR<br>GK GK