The US denied visas to DRDO chief G Satheesh Reddy and S Guruprasad, another defence scientist, earlier this month, it came to light on Wednesday. The two were to attend an Indo-Pacific conference in Hawaii. The US move, though seemingly not linked to India’s A-Sat test, has raised eyebrows in the defence establishment. “We don’t know why they didn’t get visas... they had visited US before,” a source said.