No personnel were in the area, and there appear only to be damages to today's launch site at Wallops and vehicles, according to the NASA livestream. The Antares rocket would have launched a Cygnus spacecraft to resupply the International Space Station; this would have been Orbital's third resupply mission. The rocket was carrying 1360 pounds (617 kg) of food for the astronauts aboard the ISS, as well as flight crew equipment, science equipment for the US and international science communities, spacewalk equipment and hardware.
Tomorrow, a Russian Progress spacecraft will launch to the ISS. It's not yet clear whether the botched resupply mission will mean the astronauts have to return to Earth early, or what the implications might be for a November launch of more astronauts.
Below is another view, this one from bystanders: