Texas Gov. Rick Perry has asked the US Department of Homeland Security for nearly $350 million to cover the costs he says Texas has incurred incarcerating illegal immigrants in state prisons and county jails. In a letter to Homeland Security Secretary Janet Napolitano, Perry reiterated a claim he's often leveled against the federal government: that it's not doing enough to secure the border with Mexico and as a result, has allowed illegal immigrants to enter the U.S. and use taxpayer-funded resources, including the prison system. The letter was dated Aug. 10, three days before the Republican governor formally announced he is running for president. Reached after-hours Friday by phone, DHS spokesman Matthew Chandler said he wasn't in position to comment and said he could not confirm that the DHS had even received the letter. Perry has been criticized by some fellow conservatives as being too lenient on illegal immigration issues.