BEIRUT, Sept 18 (Reuters) - Hand-held radios used by armed group Hezbollah detonated on Wednesday across Lebanon's south in the country's deadliest day since cross-border fighting erupted between the militants and Israel nearly a year ago, stoking tensions after similar explosions of the group's pagers the day before.

At least nine people were killed and nearly 3,000 wounded when pagers used by Hezbollah members, including fighters and medics, detonated simultaneously across Lebanon.The detonations started around 3:30pm (1230 GMT) in the southern suburbs of Beirut known as Dahiyeh and the eastern Bekaa valley - strongholds of the anti-Israel militant group Hezbollah.

According to reports from senior Lebanese security sources, the explosions were caused by small amounts of explosives hidden inside 5,000 Taiwan-made pagers ordered by Hezbollah five months before the incident.