MANAMA: Bahraini police fired tear gas Friday at anti-regime protesters after blocking them from marching toward armed regime loyalists, as the US defense secretary began a visit to encourage leaders to embrace reform. Robert Gates landed in Manama as tensions soared in the tiny Gulf kingdom, which is home to the US Fifth Fleet. The unannounced visit was designed to reassure Bahrain's leaders of US support while also urging a dialogue with opposition groups, press secretary Geoff Morrell told reporters aboard Gates's plane. Gates “felt it was important to make a stop in Manama to engage with the crown prince and the king of Bahrain about the current situation there as well as in the region,” Morrell said. The defense chief is due to meet officials Saturday, he said. Earlier thousands of demonstrators chanted slogans against King Hamad when riot police stopped them from marching toward a roundabout near the royal palace in Manama, where a group of pro-regime loyalists waited with clubs, swords and metal pipes. As the marchers retreated, some of the mainly Shiite protesters hurled stones at riot police, who responded with tear gas, sending demonstrators scattering. A group of demonstrators tried to restrain the stone-throwers, grabbing rocks from their hands, and protesters formed a human chain to force the crowd away from the police after the clouds of tear gas had cleared. This is the first time that clashes have occurred since the first week of protests. In the Refaa area of Manama, pro-government group chanted “the people want Khalifa Bin Salman,” referring to the long-time prime minister whose ouster the opposition demands, and “long live the Bahraini monarchy.” Many carried weapons that also included golf clubs and sticks with knives and nails embedded in them, in an ominous show of intent toward the mainly Shiite activists who had called for an anti-regime march to the palace. At one point, a group of armed loyalists sprinted out of the roundabout where they had gathered, yelling “Allahu akbar” (God is greatest), and attacked a car that was stopped in traffic. Police did not intervene.