The group sent separate death notices for each member from Wednesday evening to Thursday morning, saying they had been killed "on the road to Jerusalem" -- the phrase used by Hezbollah to refer to fighters killed by Israel.

"The 20 Hezbollah members were killed by walkie-talkie explosions" across Lebanon on Wednesday, the source told AFP, requesting anonymity to discuss sensitive matters.

Earlier Wednesday, the health ministry said the second wave of explosions of electronic devices in Hezbollah strongholds in Lebanon killed 20 people and left more than 450 people wounded.

Wednesday's blasts came a day after the simultaneous detonation of pagers used by Hezbollah killed 12 people, including two children, and wounded up to 2,800 others across Lebanon, in an unprecedented attack blamed on Israel.

Israel did not comment on the incidents.

Hezbollah chief Hassan Nasrallah is due to give his first televised speech since the attacks on Thursday afternoon.

 Discontinued devices

Japanese firm Icom said Thursday that it had stopped producing the model of radios reportedly used in recent blasts in Lebanon around 10 years ago.

"The IC-V82 is a handheld radio that was produced and exported, including to the Middle East, from 2004 to October 2014.

It was discontinued about 10 years ago, and since then, it has not been shipped from our company," Icom said in a statement.

Company executive Yoshiki Enomoto told Japanese television NTV he was “surprised” by the news. He said the company could not confirm if the unit in question was Icom-made.

“This specific device had a lot of fake copies out in the market,” he said, adding that company officials could only determine its authenticity if they see its circuits.

The company said its export models are only distributed through official sales representatives under rigid export control rules set by the Japanese Trade Ministry.