Updated 8.15pm with updated casualty figures, details.

Nine people were killed and some 2,800 were wounded Tuesday when pagers used by Hezbollah members exploded across Lebanon.

The sons of Hezbollah lawmakers Ali Ammar and Hassan Fadlallah were among the dead, a source close to the group told AFP, requesting anonymity to discuss sensitive matters.

The blasts "killed nine people, including a girl", minister Firass Abiad said in a casualty update.

"About 2,800 people were injured, about 200 of them critically" with injuries mostly reported to the face, hands and stomach, he added.

The 10-year-old daughter of a Hezbollah member was killed in east Lebanon's Bekaa Valley when his pager exploded, her family and a source close to the group said.

Iran's ambassador to Beirut was also wounded in a pager explosion but his injuries were not serious, state media reported.

In neighbouring Syria, 14 people were wounded "after pagers used by Hezbollah exploded," Britain-based war monitor, the Syrian Observatory for Human Rights said.

The Israeli military said it had "no comment", when contacted by AFP about the pager blasts.

Lebanon's official National News Agency reported "an unprecedented enemy security incident" with "handheld pagers detonating" in several regions.

"Dozens of injuries were reported," the NNA said.

Hezbollah had asked its members to avoid using mobile phones after the Gaza war began to avoid Israeli breaches of the technology.

Hezbollah members communicate through their own telecommunications system.