Washington: The US has warned Pakistan that another terror attack on India will prove to be “extremely problematic” as it asked Islamabad to take more “concrete and sustained” actions to rein in terror groups including the JeM and the LeT. Tensions between India and Pakistan escalated after a suicide bomber of Pakistan-based terror group Jaish-e-Mohammed (JeM) killed 40 CRPF personnel in Jammu and Kashmir’s Pulwama district in February 14. India launched a counter-terror operation in Balakot. The next day, Pakistan Air Force retaliated and downed a MiG-21 in an aerial combat and captured its pilot, who was handed over to India on March 1.