Baalbek (Lebanon) (AFP) - A suicide bomber on a motorcycle killed a number of Hezbollah fighters when he blew himself up close to a checkpoint in eastern Lebanon of the powerful Shite group, a security official said.

"The bomber blew himself up near a Hezbollah checkpoint in the Khraybeh area" in the Bekaa Valley, near the border with Syria, the source said.

"The Hezbollah fighters at the checkpoint were all killed" and a number more nearby were wounded, he added, without saying how many there were in total.

Lebanon's National News Agency said three people had been killed at the checkpoint, without specifying that they were fighters.

The attack comes with the already high tensions in Lebanon over the war in neighbouring Syria made worse Saturday with news that a Lebanese soldier had been executed by the Al-Nusra Front, the Syrian branch of Al-Qaeda.