Dubai police claimed Lebanese terror group Hezbollah was behind a Monday bombing in the outskirts of Bahrain’s capital Manama that resulted in the deaths of three policemen, one of them an officer from the United Arab Emirates deployed to help bolster security in the tiny island kingdom.

According to Dubai police chief Dahi Khalfan Tamim, the culprit behind the attack had traveled to Lebanon several times over the past years and had been trained by Hezbollah operatives.

“The criminal who carried out the operation to assassinate the Emirati martyr, First Lieutenant Tareq Mohammed al-Shehhi, used to go to Lebanon and was given explosives training by Hezbollah,” Khalfan said on Tuesday. Tamim went on to accuse the Bahraini opposition of siding with Iran and Hezbollah in an attempt to destabilize the Arab Gulf states.

Monday’s attack took place during a protest organized by groups associated with Bahrain’s largely Shiite-dominated opposition movement. An initial investigation suggested that the bomb was planted near a lamppost and was detonated remotely. Two other explosions occurred nearby and another bomb was defused, Bahrain’s Interior Ministry said.

In Bahrain’s three-year uprising, the opposition movement is demanding increased political rights from the Sunni monarchy. The country is a small, Western-allied island kingdom off the coast of Saudi Arabia that is home to the US Navy’s 5th Fleet.

While mainstream opposition leaders have urged their followers to keep the demonstrations peaceful, young protesters frequently clash with riot police in running street skirmishes.

Some radical anti-government factions have been increasingly using bombs targeting government forces. The weapons typically do not have the force of explosives used by insurgents in places such as Iraq or Syria, though they have resulted in a number of deaths.

The main opposition groups condemned Monday’s blast, saying that they are against all kinds of violence. Witnesses reported seeing attackers vandalizing offices of the main Shiite opposition bloc, al-Wefaq, soon after the blast in apparent retaliation for the attack.