Lebanese security forces inspect the site of a suicide car bomb attack near Nabi Uthman on March 16, 2014.

Story highlights

Two people were killed and 14 injured in a suicide bomb attack in Lebanon's Bekaa Valley

Two rebel groups fighting against the Assad regime claimed responsibility

The bomb went off near the Syrian border in a Hezbollah stronghold

Hezbollah has been supporting the Assad regime in Syria's civil war

CNN  — 

A suicide bomb explosion killed two people and injured 14 on a highway near Nabi Uthman in Lebanon’s Bekaa valley, according to Lebanon’s official news agency NNA.

The suicide bomber was speeding and raised the suspicion of a number of young men, NNA reports. When he stopped, the bomb exploded.

A group called “Free Sunni Brigade in Baalbek” was the first to claim responsibility for the bombing on Twitter.

The Al-Nusra Front in Lebanon, an offshoot of the Syrian rebel group, also claimed on Twitter that is was responsible for the suicide attack and called the “Free Sunni Brigade” a fraud.

The Free Sunni Brigade also addressed the Lebanese Army and Hezbollah saying, “Be prepared for the battle of Yabroud inside Lebanon!”

Hezbollah fighters have been helping the regime of Syrian President Bashar al-Assad in that country’s civil war.

Syrian government forces have taken full control of the embattled town of Yabroud, once considered a rebel stronghold, Syrian state TV said Sunday.

Meanwhile, the Islamic Front, an alliance of Islamist rebel groups involved in the fighting in Yabroud, said via Twitter that fighting continues at the entrance of the town and disputes government accounts that the town is in full control of the Syrian military.

Yabroud is located near the Lebanese border, is considered a vital supply route for rebels and is a key strategic access road between Lebanon and Syria.

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CNN’s Saad Abedine contributed to this report.