ISRO's communication satellites aboard a Geosynchronous Launch Vehicle (GSLV) exploded mid-air yesterday less than a minute after lift-off from the spaceport at Sriharikota and fell into the sea. GSAT-5P, carrying 24 C-band and 12 extended C-bandtransponders, aboard a homegrown vehicle GSLV F06 failed after the rocket veered from its flight path and broke into pieces.ISRO chief K Radhakrishnan told media persons that the destruct command was issued when the control and command signal failed to reach the activation system at the first stage itself. The satellite was meant for augmenting communication services currently provided by the Indian National Satellite System. Built at 125 crore rupees, it was to replace the INSAT-3E that was sent up in 2003.The rocket blasted-off at around 4 PM from the second launch pad at the Satish Dhawan Space Centre at the end of the 29-hour countdown but was hit by a snag in the first stage itself. Reconstructing the events, Radhakrishnan said when the destruct signal was given the vehicle was at an altitude of 8 km and a distance of 2.5 km away from Sriharikota. The debris have fallen in the sea.