ROME (Reuters) - At least 5 people have died in a migrant shipwreck in the central Mediterranean, Spanish charity Open Arms said on Wednesday, warning that the number of fatalities could grow as rescue operations continue. Some 100 people had been traveling for about two days on a dinghy that collapsed in international waters off Libya where it was assisted by Open Arms, the NGO said. It said it was carrying out the rescue operation on its own, with just two speed boats and six rescuers.